Science and Engineering of Superhydrophobic Surfaces: Review of Corrosion Resistance, Chemical and Mechanical Stability

Gh. Barati Darband; M. Aliofkhazraei; S. Khorsand; S. Sokhanvar; A. Kaboli

doi:10.1016/j.arabjc.2018.01.013

View/Download PDF

Buy Reprints

PDF

Translate this page into:

Review article

13 (

); 1763-1802

doi:

10.1016/j.arabjc.2018.01.013

Science and Engineering of Superhydrophobic Surfaces: Review of Corrosion Resistance, Chemical and Mechanical Stability

Gh. Barati Darband^{^a}, M. Aliofkhazraei^{^a,⁎}, S. Khorsand^{^b}, S. Sokhanvar^{^a}, A. Kaboli^{^a}

a Department of Materials Engineering, Tarbiat Modares University, P.O. Box: 14115-143, Tehran, Iran

b Brunel Centre for Advanced Solidification Technology (BCAST), Brunel University London, Uxbridge, Middlesex UB8 3PH, UK

⁎Corresponding author. maliofkh@gmail.com (M. Aliofkhazraei) khazraei@modares.ac.ir (M. Aliofkhazraei)

Received: 2017-10-26, Accepted: 2018-1-23, Published: 2018-01-01

Disclaimer:
This article was originally published by Elsevier and was migrated to Scientific Scholar after the change of Publisher.

Peer review under responsibility of King Saud University.

Abstract

Investigations on superhydrophobic surfaces (SHS) are very interesting because of their importance in many applications. One of the major applications of these SHS is to increase the corrosion resistance of surfaces exposed to corrosive environments as well as their long-term chemical stability and maintaining the superhydrophobic characteristics. Deep understanding of how to increase the corrosion resistance by SHS has a significant effect on the development of strategies to improve corrosion resistance and long-term chemical stability of these surfaces. Other important properties that limited the real use of superhydrophobic surfaces are mechanical stability. In this review article, an overview of SHS is provided, and then their fabrication methods discussed. Moreover, the corrosion resistance of these SHS fabricated by various methods and their chemical stability and mechanical stability are reviewed. -In the following, recent strategies for improvement of corrosion resistance, chemical and mechanical stability are reviewed.

Keywords

Chemical durability

Corrosion resistance

Mechanical stability

Superhydrophobic surfaces

Show Related Articles from PubMed

1 Introduction

Wettability of solid surfaces attracts many attentions both in research and practical applications. Studies conducted on the superhydrophobic surfaces have grown dramatically since 2004 and several review articles have been published about different aspects of superhydrophobic surfaces (Chu and Seeger, 2014; Ragesh et al., 2014; Bagheri et al., 2018; Shin et al., 2016; Simpson et al., 2015; Su et al., 2016; Tam et al., 2016 ). Basically, superhydrophobic surfaces are described by static contact angles higher than 150° and sliding angle less than 10°. It is well known that the wettability of a solid surface is a function of two primary factors including surface roughness and surface chemistry. The chemical composition of the surface determines the surface energy, which has a great effect on its wettability. However, only changing the surface chemistry cannot determine the superhydrophobic state, and these two factors must exist simultaneously (Woodward et al., 2000). The surface topology also has a significant effect on the superhydrophobic nature of the surface. Surface roughening by increasing the solid-liquid interface also increases the superhydrophobic state. By controlling these two parameters, numerous methods were developed to fabricate SHS including template based (Barshilia et al., 2012; Victor et al., 2012), electrospinning (Gu et al., 2010), sol-gel (Lakshmi et al., 2011), layer by layer (Zhao et al., 2012), etching (Yin et al., 2012b), and electrochemical deposition (Crick et al., 2013) methods, etc.

Superhydrophobic coatings have found many applications in industry including anti-fog coating, anti-freeze surfaces, oil and water separation, anti-bacterial surfaces, and medical applications. Improving corrosion resistance is one of the most important current problems of society causing large damages (Bagheri et al., 2017; Forooshani et al., 2017). In general, corrosion damage cannot be stopped completely, but there are many methods for decreasing it; e.g., cathodic and anodic protection, using protective coating to reduce the corrosion rate. One of the important coating methods to reduce the corrosion rate of surfaces is to use superhydrophobic coatings. Basically, it is believed that by creating an air layer between the surface and corrosive environment, SHS prevent contact between the corrosive ions and surface. In addition, these surfaces, reduce the portion of real contact between the corrosive electrolyte and surface, and thereby increase the corrosion resistance. However, most of the superhydrophobic surfaces lose their superhydrophobic characteristics once exposed to chemical environment and they do not have enough long term stability. Another factor that makes it difficult to use SHS is the long-term chemical stability. Most of the superhydrophobic surfaces once exposed to the chemical environment lose their superhydrophobic characteristics. Thus, nowadays, the strategies for improving the long-term chemical stability are among the most important challenges. Moreover, when the SHS influenced by abrading forces, the wetting model is changed from Cassie-Baxter to Wenzel, thus the liquid will penetrate inside the surface pores and cracks and superhydrophobicity with low hysteresis angle is destroyed. Therefore, mechanical durability is one of the other important factors which cause the limitation of real use of SHS.

Based on mentioned difficulties with the real use of superhydrophobic surfaces, the corrosion resistance of SHS fabricated by different methods, long-term chemical stability, mechanical durability and recent developments in techniques developed for improving corrosion resistance, chemical stability and mechanical durability are reviewed in this paper.

2 Wetting phenomena

2.1

2.1 Wettability

Wetting of solid surfaces by liquid materials is an important aspect of materials science and surface chemistry, and in clues in practical applications in everyday life and industry. Ideally, once a drop is placed on a surface, it forms a sphere or wets the surface completely. The first and second cases are called anti-wetting and super wetting, respectively (Durand et al., 2011).

In wetting studies, usually the contact angle is one of the most important data showing the amount of the wetting value when a liquid and solid are in contact with each other. Consider a drop of liquid placed on a horizontal surface (Fig. 1). The contact angle is defined as the angle formed by the intersection of the solid, liquid, and solid-gas interface. Fig. 1 shows that the small contact angle is formed when the liquid is distributed on the surface, while large contact angles are formed when there is lower contact area between solid and liquid (Yuan and Lee, 2013).

Illustration of contact angles formed by sessile liquid drops on a smooth homogeneous solid surface (Yuan and Lee, 2013).

2.2

2.2 Requirements for fabrication of SHS

SHS have been considered as important subjects in recent decades. These coatings can be applied on any surface, and this is one of the features that made them attractive. For the first time, SHS were widely industrially applied in highway speed cameras in Germany (Kavale et al., 2011; Mohammadi et al., 2004). Surface free energy, surface roughness, and homogeneity are three important factors in controlling the wettability, where the impact of the first two factors is more important. Surface structures/roughness able to trap a high amount of air in order to stabilize the Cassie-Baxter state. The maximum wettability angle obtained for water on a flat surface by reducing the surface energy was about 120°. Fabrication of uneven structure is necessary to reach higher angles. By taking various approaches, we can fabricate rough surfaces with low surface energy as their wettability angle is reported up to 170° (Ma and Hill, 2006; Onda et al., 1996; Shibuichi et al., 1996 ).

2.2.1

2.2.1 Surface energy

The decrease in surface energy is very common to achieve the superhydrophobic surfaces. Surfactants are used for lowering the surface energy. These compounds have a variety of different types and applications. Silane groups are greatly considered for reducing the surface energy. In silane groups, fluoroalkylsilanes are paid most attention, because, among the identified compounds, it has the greatest impact on reducing the surface energy. Due to the simultaneous presence of CF2 and CF3 groups, these compounds are very efficient. On the other hand, due to their high cost and hazards bringing to the environment by the presence of fluorine, researchers are looking for alternative substances (substances such as stearic acid and polymers) (Genzer and Efimenko, 2006; Yao and He, 2014).

2.2.2

2.2.2 Surface roughness

An uneven surface is imperative to achieve superhydrophobic property. Since in such surfaces, air bubbles are caught in the ups and downs of the surface, when water is put on the surface, it does not contact with all surface points. Due to low energy of surface and the presence of air, water does not penetrate into the valley and consequently, the surface area is reduced which results in a reduction of friction (Fig. 2). As a result, droplets slip on the surface easily (Onda et al., 1996; Shibuichi et al., 1996). Methods for fabrication unevenness can be divided into two bottom-up and top-down classifications. In the bottom-up approach, usually, nanoparticles are used as the main constituents. In the top-down approach, some methods such as etching and lithography with or without a mask are used to fabricate the cover. Recently, processes which considered combining these two methods are receiving more interest (Yao and He, 2014).

Trapped air between liquid and solid phases.

2.3

2.3 Wetting models

Before discussing the SHS, firstly wetting and different theoretical models are described. Here, the original models for wetting are presented and simple principles of each model are discussed. The first model was introduced in 1805 by Young (Good, 1952; Young, 1805; Zhao et al., 2005a,b ). For a drop of liquid on an ideal flat surface (Fig. 3a), in this model, wetting is defined by the surface free energy of a solid and derived by Eq. (1) according to Young’s equation:

(1)

\cos θ = \frac{γ_{sv} - γ_{sl}}{γ_{lv}}

where, γ is the surface tension, which represents energy per unit area. As shown in this equation, the surface energy is proportional to the contact angle. It can be said that Young angle is fabricated by thermodynamic equilibrium of free energy surfaces at the solid-liquid-gas interface. Since the actual surfaces usually have different surface conditions and surface roughness of solid plays a significant role in determining the wettability, most of the contact angle states, in practice, cannot be fully explained by Young's equation. In 1936, Wenzel suggested an equation where the surface roughness and surface energy are associated with the contact angle according to Eq. (2) (Wenzel, 1936).

(2)

r (γ_{sv} - γ_{sl}) = γ_{lv} \cos θ_{w}^{*}

where

θ_{w}^{*}

is Wenzel’s contact angel affected by surface roughness and r is a roughness parameter. Modified Wenzel’s equation is:

(3)

\cos θ_{w}^{*} = r \cos θ

In Wenzel equation, it is assumed that the liquid passes into the grooves of the surface roughness (Fig. 3b), so the Wenzel’s equation is related to the homogeneous wetting regime (Marmur, 2003). The Wenzel equation cannot also explain the possibility to obtain superhydrophobic properties from hydrophilic materials or even superoleophobic properties from oleophilic materials. Wenzel equation represents that roughness modifies the wettability and anti-wettability, depending on the nature of the surface. Therefore, when the contact angle of the flat surface is greater than 90°, the surface roughness increases the contact angle and if the θ angle is less than 90°, the increase in surface roughness reduces the contact angle (Blossey, 2003). Wenzel model is only practical and workable for the homogenous interfacial areas, and cannot be applied to the non-homogeneous surfaces. In this regard, Cassie and Baxter in 1944 provided another model for heterogeneous surfaces (Fig. 3c). Their model consists of two parts. The first part includes surface fraction, f_1, and contact angle of θ₁ and the other part includes f₂ and $θ_{2}$ (Cassie and Baxter, 1944). Hence, in Cassie and Baxter’s equation, the contact angle is defined as Eq. (4):

(4)

\cos θ = f_{1} \cos θ_{1} + f_{2} \cos θ_{2}

where θ is the contact angle in the model of Cassie and Baxter and f_i is the fraction of surface area with contact angle θ_i (f₁ + f₂ = 1). In Cassie and Baxter’s model, it is assumed that the liquid is in contact with the solid only at the roughness tips and it is assumed that air pockets are trapped below the liquid. In this case, it can be considered that a part of the surface where the air is trapped in, is not wetted by the liquid. If only air is present between solid and liquid, θ₂ will be 180°. Therefore, Eq. (4) can be written as Eq. (5):

(5)

\cos θ_{CB} = f_{s} (\cos θ_{s} + 1) - 1

where f_s is the fractional solid surface with a contact angle of θs. In addition to the models listed, more improved models have been provided in references to predict the specific modes of wetting (Erbil and Cansoy, 2009; Jung and Bhushan, 2009; Koishi et al., 2009; Lundgren et al., 2007; Reyssat et al., 2007; Vrancken et al., 2009 ).

2.4

2.4 Rolling angle and the wetting angle hysteresis

Rolling angle is the lowest horizontal angle to the in which the droplet began to move on the surface and rolls on it. For SHS, this angle should be less than 10° as well as hysteresis less than 10°. For studying the behavior of surfaces, in addition to the measurement of contact angle and rolling angle, determining the wetting angle hysteresis is also important, which is the difference between the advancing angel and receding angel. As shown in Fig. 4, while rolling, the contact angle in front of the drop is larger than behind. Difference between the advancing and receding angles of drop is introduced as hysteresis of contact angle.

(a) Schematic illustration of contact angle hysteresis on a tilted surface, (b) advancing and receding contact angles on a flat surface via increasing and decreasing the volume of droplet, respectively (Yao and He, 2014).

3 Application of superhydrophobic surfaces

Up to now, many SHS with proposed applications have been fabricated by different methods. In this part, the main applications of these surfaces are discussed briefly. A schematic of the main applications of SHS is shown in Fig. 5. In the next part, the corrosion resistance of surfaces, chemical and mechanical stability of SHS which is the main subject of this study will be discussed in more details.

Schematic of important applications of superhydrophobic surfaces.

3.1

3.1 Increase of corrosion resistance

Corrosion is known as one of the most important problems in our societies. Since this phenomenon brings about large damages, the increase of surface corrosion resistance has attracted so much attention. Numerous methods have been applied to prevent or reduce the corrosion rate of surfaces. But, recently superhydrophobic coatings are introduced to prevent corrosion rate by applying on the whole range of metals such as aluminum (Barkhudarov et al., 2008; Hintze and Calle, 2006; Skorb et al., 2010 ), copper (Cui et al., 2009; Zhang et al., 2008b), magnesium (Ishizaki and Saito, 2010), steel (Luo et al., 2008), titanium (Zhang et al., 2011), and zinc (Hermelin et al., 2008; Ning et al., 2011).

3.2

3.2 Anti-fogging surfaces

Generally, the vapor is created on different substrates such as mirrors, glass, and other substrates, which would cause unknown risks and problems in daily life and industrial applications. This problem can be resolved by controlling the reaction between the substrate and liquids. Briefly, these strategies include superhydrophilic layers (with zero contact angle) (Dong et al., 2010; Lu et al., 2011; Luo et al., 2008; You et al., 2011 ), SHS with contact angle higher than 150°, and hydrophilic/oleophobic layers (Howarter and Youngblood, 2007, 2008).

3.3

3.3 Anti-bacterial surfaces

One of the main concerns in many industries including the medical industry is the environmental pollution of materials and equipment. The growth of biofilms as a natural spontaneous phenomenon can become a problem in the case of hospital infections. To kill the biofilm or reduce their adhesion, two strategies of bactericidal surfaces and anti-bioadhesion surfaces are considered; and the SHS are also used for this purpose.

3.4

3.4 Anti-icing surfaces

Formation of ice on the substrates exposed to the environment can interfere the functioning of many industries, such as highways, aircraft, shipping, and the communications equipment. Many of the strategies for elimination of this problem involves removal of ice in the physical or chemical form which causes damage and consumes so much energy. Recently, SHS on substrates of aluminum (Jung et al., 2012; Kulinich et al., 2010; Kulinich and Farzaneh, 2009a, 2009b ), copper (Tourkine et al., 2009), and steel (Meuler et al., 2010) have been used to fix the problem. Due to the extraordinary properties of SHS, they can prevent the formation and accumulation of ice on the surfaces.

3.5

3.5 Oil and water separation

Due to the increase in industrial water laden with oil, separation of oil and water mixture has become one of the global challenges. The combination of superhydrophobic and superoleophilic (Gui et al., 2011; Pan et al., 2008; Wang et al., 2009, 2006c ), superhydrophilic and under water superoleophobic (Liu et al., 2009b; Tian et al., 2012; Wen et al., 2013 ), and superhydrophilic and superoleophobic (Darmanin et al., 2014a, 2014b; Kota et al., 2012 ) are used to separate oil and water. By the use of different strategies, a series of materials such as membranes, tissues, foams, and sorbents have been developed for separating water and oil.

3.6

3.6 Self-cleaning surfaces

Self-cleaning surfaces have a large number of applications in everyday life, agriculture, industry, and military industries. Recently, many methods and strategies have been used to fabricate self-cleaning surfaces (Blossey, 2003; Liu and Jiang, 2011; Parkin and Palgrave, 2005; Sanchez et al., 2005 ). Many of the self-cleaning coatings such as glasses, tiles, and tissues have been industrialized. Self-cleaning surfaces could be made using the superhydrophobic surfaces.

3.7

3.7 Drag reduction

Drag is one of the main obstacles for aircraft, submarines, and shipping equipment. Inspired by nature, we can find several ways to reduce and optimize drag value. Basically, methods for fabrication of drag-reducing coatings are inspired by lotus plant's leaves (Rothstein, 2010; Truesdell et al., 2006). At the SHS, drag reduction can be connected to the water-repellent properties, where a gas film is formed between the water and the surface which reduces the contact between water and the solid substrate.

3.8

3.8 Battery manufacture technology

Battery manufacture technology is a major research challenge in electronics due to insufficient capacity and lifetime of batteries in pursuit of the achieved advances in semi-conductors technology (Lifton et al., 2005). A battery may supply the required amount of energy and have an acceptable performance when it is able to endure long capacitation periods. A simple mechanical separator is used in common batteries for separation of the electrolyte and electrode which leads to increase in excessive size of batteries.

3.9

3.9 Sensors

Due to their specific chemical composition, superhydrophobic films may have various types of interactions with different materials in liquid and gas media. Additionally, sensors equipped with superhydrophobic properties are highly accurate because of their roughness. This feature was investigated in many cases (Andreeva et al., 2012; Cho et al., 2013; Lv et al., 2012 ). For instance, Saito et al. employed a superhydrophobic quartz crystal balance for identification of volatile organic compounds (Wang et al., 2011b). Several organic substances such as toluene and formaldehyde with van der Waals interactions lead to increase in weight through SHS made of trimethylmethoxysilane by means of superhydrophobic CVD coating. Other research groups have also investigated SHS produced by amine agents incorporating carbon dioxide (Hassan et al., 2012). In metallic nanostructures, coherent fluctuations in electrons conduction band may lead to extreme plasmon resonance in the local electromagnetic field. This effect, called surface enhanced raman scattering (SERC), is used for identification of metallic particles in a solution (Wang et al., 2011b). Lee et al. (Xu et al., 2011a), studied the effect of increase in SERS in SHS made of ZnO nano-bars and coated with silver nanoparticles. Signal increase was observed to be three times more than a normal surface.

Most of biological systems are known to have complicated bonds such as specific hydrogen bonds. For instance, protein-carbohydrate interaction is a significant challenge in many vital biological processes such as signaling, recognition and decomposition (Williams and Davies, 2001) On the other hand, development of sensors based on carbohydrate testing is of great importance in medical, diagnosis and treatment applications. Lee et al. (Qing and Sun, 2011) reported the feasibility of acquiring SHS with variable wettability in presence of saccharide. The implemented co-polymer comprised N-isopropylacrylamide and a phenyl acid derivation. Polymerization caused the micro and nano-structures obtain superhydrophobic properties. Wetting properties changed with immersion in glucose from super hydrophobicity to superhydrophobocity due to interaction between the polymer and glucose. The role of superhydrophobic surfaces in performance improvement of different types of sensors has been widely studied.

3.10

3.10 Water purification

In recent years, photocatalytic approaches were used for removal soluble pollutants in water by means of optical energy (Zhu et al., 2017; Zou et al., 2016) Superhydrophobic substances, made of titania nanoparticles and semi-conductive ceramic materials possess photocatalytic properties were used for removal of soluble pollutants in water (Darmanin and Guittard, 2014; Cao et al., 2009) produced superhydrophobic In(OH)₃ nano-cubes by hydrothermal procedure. They reported that these nano-cubes demonstrated excellent photocatalytic activity under ultraviolet beams. Destruction rate of rhodamine B (RhB) reached 93.25% after 16 h when In(OH)₃ nanocubes were introduced. In addition, Wang et al. (2011c) reported photocatalytic activity by Cu/PANI superhydrophobic nanocomposites under ultraviolet beams. After addition of Cu/PANI, destruction rate of RhB reached 97% only in 35 min.

3.11

3.11 Optical devices

A surface structure is required to achieve superhydrophobic films. Optical properties depend on the surface structure. Superhydrophobic films and surfaces possess various structures and other features including self-cleaning, anti-dust, anti-mist, etc. have also been studied in different terms of optical properties (Lin et al., 2017; Lomga et al., 2017; Martin and Bhushan, 2017; Nakate et al., 2016 ). Depending on roughness and light scattering, surface structure may reduce clarity; while, this feature is necessary in several applications such as glasses, optics, and cameras (Rahmawan et al., 2013). For superhydrophobic film required along with clarity, surface roughness has to be less than visual light wavelength. Hence, most of superhydrophobic films with high clarity are produced using nanoparticles (SiO₂, TiO₂, zinc oxide, C, polymer) through electrospinning, sol-gel process, vapor deposition or cloud lithography (Bravo et al., 2007; Zhu et al., 2014).

Superhydrophobic films are used for performance improvement in other optical applications like light luminance (Nakate et al., 2016; Tarwal et al., 2013), photon crystals (Bao et al., 2016; Goodwyn et al., 2009) and solar cells (Xu et al., 2016b).

3.12

3.12 Membrane distillation and water desalination

Seawater desalination systems are used all over the world particularly in countries that suffer deficiency of drinkable water. There are several industrial techniques for water desalination including flash distillation, reverse osmosis and membrane distillation. In the latter, a hot mass of vapor with non-volatile species is passed through a suprhydrophobic membrane. A cooling flow is placed on the other side of the membrane. This method is usually carried out by low flux in limited membrane and precipitants which both depend on the microstructure and constituents of the membrane. If the porous membrane is made with superhydrophobic surfaces, the allowed pores size may be increased so that the passing flux is escalated (Fan et al., 2017; Ma et al., 2009). Superhydrophobic membranes have been created using various materials and techniques to improve the performance of water desalination systems (Fan et al., 2016a; Ren et al., 2017). Generally, it may be concluded that application of superhydrophobic properties in water desalination systems is a promising technique leading to performance improvement and reduction of consumed energy which consequently will make these systems more environmentally compatible.

3.13

3.13 Microfluidic devices

Liquid flow and penetration control is highly important in microfluidic devices. Most of studies were conducted on transfer properties of microfluidic devices based on application of liquid penetration in microfluidic systems. Hence, there have been many studies on reduction of flow drag on a surface, bar or canal which affects the required energy and flow rate. The drag force is caused by the shear stress between the flow and surface (Darmanin and Guittard, 2014). Superhydrophobic properties may help in reduction of the drag force through capabilities such as entrainment of air on surface (cassie-baxter state) so that liquid transfer and penetration control is facilitated in microfluidic systems (Abramov et al., 2012; McHale et al., 2011).

3.14

3.14 Other applications

In addition to these main applications of SHS, regarding the industrial development and the emergence of new methods for fabrication SHS, other applications will already be found for the SHS. Some of other applications can be noted in medical sciences (Bormashenko and Bormashenko, 2011; Song et al., 2010; Yohe et al., 2012 ). Moreover, water shortage on the earth and the unavailability of healthy drinking water is one of the today's challenges. Again inspired by nature, we can fabricate alternative methods to directly withdraw water from the atmosphere and resolve water scarcity in many regions of the world. This goal is achievable by using a different surface with various wettability (Choi et al., 2009; Garrod et al., 2007; Zhai et al., 2006 ). Furthermore, using the technology of SHS allows applying the printing and reprography. Since wettability of surface plays a major role in this industry, extensive studies have been conducted on this topic (Cui et al., 2009; Zhao et al., 2009).

4 Fabrication of SHS

Generally, as noted earlier, methods for fabrication SHS are inspired by nature. To achieve SHS, we should increase the surface roughness and reduce the surface energy. Thus, it can be concluded that trend of fabrication of SHS can be achieved by either roughening the surface of a material with low surface energy or reducing the surface energy of a rough material or both of them. Therefore, methods that have been created for fabrication of superhydrophobic surfaces can be divided as follows. Schematic figure showing general methods of fabrication SHS are shown in Fig. 6. In this section, these methods are briefly discussed.

Schematic of different methods of fabrication superhydrophobic surfaces.

4.1

4.1 Sol-gel method

Sol-gel is one of the most popular methods for applying mineral coatings with the benefits such as low-temperature process, the simplicity of the technique, low cost, and simple control of the process (Hench and West, 1990). This method is used to fabricate SHS on various oxides such as silica, alumina, and titania based on theories of Wenzel and Cassi Baxter (Hikita et al., 2005; Jitianu et al., 2010; Mahltig and Böttcher, 2003; Pilotek and Schmidt, 2003; Wu et al., 2005; Yu et al., 2007 ). By controlling sol-gel variables such as composition of precursor’s solutions, hydrolysis, and polycondensation processes, the films would have different morphologies and surface energies. Since this method is compatible with glass, it is used for fabrication of transparent superhydrophobic coatings on the glass (Rao et al., 2009; Shang et al., 2005; Tadanaga et al., 2000 ).

4.2

4.2 Electrospinning

Electrospinning is a simple and versatile method to fabricate continuous polymer fibers in micro or nanometer sizes (Ma et al., 2005a; Wang et al., 2008). Using this method and roughening approach, it is possible to fabricate the SHS (Tuteja et al., 2007). By adding polymer to the precursor's solution, it is also possible to fabricate inorganic fibers using electrospinning method. The existence of polymer can change the viscosity, surface tension, conductivity, and other properties of electrospinning as these cases are essential for electrospinning process. In order fabricate uniform fibers, polymer molecular weight and solution concentration should be selected properly (Ma et al., 2005b).

4.3

4.3 Electrochemical methods

Many processes have been used to control surface roughness and surface morphology. But, comparing with other methods, electrochemical deposition process offers a feasible way to control growth kinetics of deposits and also allows to simply obtaining large surfaces with different morphologies. In fact, electrochemical methods are simple, rapid, and highly repeatable. In addition, unlike many other techniques, using electrochemical methods, it is possible to fabricate different morphologies such as needles, fibers, tubes, dendrites, and sheets (Darmanin et al., 2013). Electrochemical methods include electrochemical deposition, anodic oxidation (Shibuichi et al., 1998; Tsujii et al., 1997), and polymerization reactions (Li and Shi, 2005; Nicolas et al., 2006; Yan et al., 2005 ), and the reaction of galvanic cells (Shi et al., 2006; Wang et al., 2006a) are used frequently to fabricate superhydrophobic surfaces (Jiang et al., 2005; Yu et al., 2005; Yu et al., 2006 ). Jiaming et al. (Ye et al., 2009) investigated the relationship between different structures and wetting properties on the aluminum substrates using electrochemical anodic oxidation method. The relationship between the honeycomb the bird's nest structures and superhydrophobicity was also reviewed, where the results showed that fabrication of the bird's nest structure is essential for fabrication of superhydrophobic surface. Oikawa et al. (2009), fabricated superhydrophobic porous anodic layer with porosity dimensions around 10 nm by anodic oxidation method with a wetting angle of 158° on niobium.

4.4

4.4 Layer-by-layer method

The layer-by-layer technique is widely used for fabricate of various nano- and microstructures as well as fabricating superhydrophobic surfaces (Han et al., 2005; Shi et al., 2005; Zhao et al., 2005a,b ). The main principle of this method is changing the substrate surface charge that leads to the fabrication of multi-layer films (Chen and McCarthy, 1997). In this method, in order to improve the wettability of fabricated films, nano or microparticles are added to increase the surface roughness of the film. One advantage of this method is the precise control of the thickness of the coating, so it is the perfect method to fabricate transparent surfaces. Moreover, this method is used to fabricate superhydrophobic surfaces on non-flat surfaces (Zhang et al., 2008c).

4.5

4.5 Plasma techniques

Plasma is a simple and effective technique to fabricate hydrophobic surfaces. Using this method, it is possible to reduce surface energy and increase the roughness of the surface at the same time. Superhydrophobic surfaces can be easily achieved using oxygen plasma. However, ageing is the main problem of superhydrophobic surfaces fabricated by plasma technique. Since the roughness of surfaces fabricated by the plasma can be easily adjusted, this method is appropriate way to fabricate superhydrophobic coatings with special optical properties, where the surface roughness of these coatings is the most important factor (Zhang et al., 2008c). Up to now, a plenty of works have been reported to fabricate superhydrophobic coating of fluorine using plasma techniques (Coulson et al., 2000; Morra et al., 1989; Woodward et al., 2003; Youngblood and McCarthy, 1999 ).

4.6

4.6 Other important methods

In addition to the mentioned methods for fabrication of superhydrophobic surfaces, there are also many other methods applicable. These methods include vapor deposition techniques such as physical vapor deposition (PVD) and chemical deposition which allows creating highly controlled regular nanostructures (Akram Raza et al., 2010; Du and He, 2011; Xu et al., 2009 ). In this regard, spray technique is another technique which is frequently used to fabricate superhydrophobic surfaces. Furthermore, spin-coating method is another method for fabrication superhydrophobic surfaces that allow preparing uniform film with hierarchical nanostructures and microstructures (Liu et al., 2008). Also, various structural patterns can be used as a template to obtain surface roughness and superhydrophobic surfaces, that are known by the name of the template (Feng et al., 2002). Using the instability of multi-component mixtures, especially in the case of polymers and using phase separation method, also makes it possible to fabricate superhydrophobic surfaces.

5 Corrosion resistance of SHS

Generally, it is believed that fabrication of superhydrophobic coating on the surfaces protects them from environmental moisture and inhibits the electrochemical reactions. This can improve the corrosion resistance of the surface in highly aggressive media. In other words, superhydrophobic surfaces can be used as a solution to decrease the corrosion of the metal substrates, such as magnesium, aluminum, copper, zinc, nickel and steel alloys. The anticorrosion mechanism of the superhydrophobic surfaces is considered in this section. Many techniques of fabrication superhydrophobic surfaces, as well as various methods of characterization and analysis were applied in literature, but their conclusion was the same; superhydrophobic coatings prevent metallic substrates from corrosion attacks (Ishizaki et al., 2010). As mentioned in Section 2.2, the requirements for fabrication superhydrophobic surfaces are preparing micro and nano-roughness on the surface and decrease of surface energy. When the surface is roughened, large peaks are formed on the surface associated with numerous valleys placed between them. The inhomogeneity of the superhydrophobic coatings allows air to be trapped easily within the valleys between the peaks of the rough surface. Consequently, the aggressive ion species such as Cl⁻ in the electrolyte or corrosive environments can rarely attack the underlying surface owing to the obstructive influence of trapped air. In fact, the air trapped on the superhydrophobic surface acts as a passivation layer and prevents substrate from corrosive processes. When smooth metals are exposed directly to the environment containing corrosive species, the aggressive ions can easily corrode the surface. While, in superhydrophobic surfaces, the air trapped in the surface grooves can hinder direct contact between the corrosive media and the material. The superhydrophobic structure would permit an enhancement of the surface air fraction in the valleys and also decrease the actual area of rough surface in contact with aggressive solution (Ishizaki et al., 2010, Radwan et al., 2015; Boinovich and Emelyanenko, 2012 ).

Capillarity is another important factor that explains why super-hydrophobic surface can improve the corrosion resistance of metals and was introduced by Liu et al. (Liu et al., 2007a). The height (h) of the water column within the tube can be calculated by the following equation:

(6)

h = \frac{2 γ \cos θ}{ρ gR}

where γ is the surface tension, θ is the contact angle, ρ is the density of the liquid, g is the gravity acceleration and R is the radius of a cylindrical tube. SHS is considered as a vertical cylindrical tube dumped in the liquid. The water contact angle of the super-hydrophobic surface is higher than 150° and the pore diameter is very small. As a result, the corrosive liquid can be forced out of the pores of superhydrophobic surface by the Laplace pressure and thus, the substrate could be perfectly protected from corrosion in the aggressive environment.

Schematic of the mechanism of increasing resistance to corrosion of fabricated superhydrophobic surfaces is shown in Fig. 7. In this section, the corrosion resistance of fabricated superhydrophobic surface by different methods will be reviewed to compare the corrosion resistance. Several works have been carried out in order to study the corrosion resistance of superhydrophobic surfaces. In the next sections, some of the results obtained by different methods will be discussed.

Schematic of corrosion resistance improvement by superhydrophobicity.

5.1

5.1 Electrodeposition method

Firstly, the corrosion resistance of fabricated superhydrophobic coating using electrodeposition method will be studied. Compared to many other methods, electrodeposition do not require long-term conditions such as exhausting chemical treatment, expensive materials, complex multi-stage procedures, and expensive equipment (Chen et al., 2012; Liu et al., 2014b, 2014c; She et al., 2012 ).

Wang et al. (Wang et al., 2011a), prepared superhydrophobic coating as a corrosion barrier using an single-stage electrodeposition method. In their study, zinc tetradecanoate film was formed on the substrate by two-electrodes arrangement, with the zinc sample used as the anode and platinum serve as the cathode. Film was formed on the surface by electrochemical method at potential of 30 V for 2 h at room temperature by direct current power supply. The corrosion resistance of fabricated coating was studied and corrosion test results demonstrated that form of superhydrophobic coating on the surface significantly increased the corrosion resistance of the substrate. In addition, the trapped air acted as dielectric film as a pure capacitor with parallel plates that would prevent the transfer of electrons between the substrate and the electrolyte and as a result improve the corrosion resistance of the substrate. In another study (Wang et al., 2013), the zinc-laurylamine complex film was applied with superhydrophobic properties on a zinc substrate via the electrodeposition method and the corrosion resistance of the fabricated film in the marine atmosphere simulated environment was investigated. Results of this study indicated that the fabricated superhydrophobic coating possesses significant corrosion resistant, with the corrosion inhibition efficiency reaching more than 99%.

Wu et al. (Wu et al., 2014b) fabricated the superhydrophobic silica film on the steel surface using the electrical deposition method, resulting in simultaneous fabrication of low energy and rough surface for improving the corrosion resistance properties. Corrosion resistance of the surface was studied by electrochemical impedance spectroscopy (EIS) method and a significant improvement in corrosion resistance was found because of the fabrication of superhydrophobic surfaces on the substrate.

Liu et al. (Liu et al., 2015a, 2015c) fabricated a superhydrophobic coating to improve the corrosion behavior on the copper substrate using an electrochemical method. Corrosion behavior of fabricated coating was studied using polarization and EIS methods. Results of polarization and EIS studies showed a significant improvement in corrosion resistance by applying the above hydrophobic film on the surface of the copper substrate. Mechanism of protection against corrosion by the superhydrophobic film was presented in Fig. 8. As shown in this figure, the unique SHS entraps a considerable amount of air, thus, it would prevent the wettability of the surface and significantly reduce the actual contact area between the liquid and the surface. Consequently, the air layer fabricated on the surface prevents the formation of a closed circuit and significantly improves the corrosion behavior.

Schematic illustrations of a water droplet on the super-hydrophobic film: (a) the model of a water droplet on the surface and (b) a drop of water in contact with the surface with electrodeposition 30 min at 20 V DC voltage (Liu et al., 2015c).

Fabrication of SHS leads to uniform corrosion and reduces the corrosion rate of the substrate. Fig. 9 shows the potentiodynamic polarization curves of samples of uncoated copper (BS) copper samples with the SHS (SS) and deaerated SS (DS) sample. The superhydrophobic coating was created on a copper substrate using the electrochemical method. As it could be seen, in the copper substrate without coating, the anodic branch can be divided into three distinct zones. In the first area increase in the current can be taken up to the maximum current density due to the dissolution of copper to Cu⁺ according to the Eq. (6). Then in the second area, current density would be decreased until the minimum value, caused by the formation of CuCl according to the Eq. (7) and in the third area, increase of current density was happened according to the Eq. (8) (Zhang et al., 2009).

(7)

Cu \to {Cu}^{+} + e^{-}

(8)

{Cu}^{+} + {Cl}^{-} \to CuCl

(9)

CuCl + {Cl}^{-} \to {CuCl}_{2}^{-}

Polarization curves of BS, SS and DS in 3.5 wt% NaCl solution (Wang et al., 2010b).

By applying the superhydrophobic coating on the surface, corrosion resistance was increased while the anodic and cathodic polarization currents decreased. The important point noted after the test was about the durability of the superhydrophobic state after applying polarization test, which reflects the high stability of the coating in the presence of chlorine ions. It was seen that corrosion resistance of DS sample was slightly increased, suggesting that the presence of the air layer is essential to improve the corrosion resistance of the coating (Wang et al., 2010b).

Most of the studies conducted on the corrosion resistance of the superhydrophobic surfaces were taken regardless of the type of contact between the electrolyte and the hydrophobic surface, while the type of contact is also important and should be considered. In this regard, Wang et al. (Wang et al., 2012a) used the synthesized 3-undecyl-4-amino-5-mercapto-1,2,4-triazole (UAMT) for fabrication the superhydrophobic coating on the copper. They fabricated superhydrophobic coatings using the single-step electrodeposition method and studied the corrosion resistance of coating under different modes (Cassie and Wenzel). Based on the results of their study, depending on the depth of immersion in the electrolyte, the fabricated superhydrophobic film can contact the NaCl solution in two cases: Cassie and Wenzel. Such contact mode leads to different mechanisms of corrosion protection. It was concluded that superhydrophobic film fabricated in the Cassie condition shows better corrosion resistance properties, because of the trapped air.

One of the main problems of fabricated superhydrophobic coatings on surfaces is about their low mechanical durability. Although numerous superhydrophobic surfaces were made using different methods, few studies reported the applications of these coatings in the industry due to their poor wear properties and low chemical stability of these coatings.

Thus, obtaining excellent mechanical properties and excellent chemical stability is the main requirement for application of these surfaces (it will be discussed in detail in Sections 6 and 7). In this regard, few studies have been conducted for investigating the mechanical stability (Lee et al., 2012; Zhu et al., 2011, 2012 ), chemical stability (Boinovich and Emelyanenko, 2012), and long-term stability (Hao et al., 2012) of these surfaces. Accordingly, abrasion resistance and excellent corrosion resistance are among the main requirements for resolving this solution and fabrication the superhydrophobic coatings with proper abrasion and corrosion resistance properties, in this regard, Su et al. (Su and Yao, 2014) developed superhydrophobic coatings with high wear resistance and excellent corrosion resistance on a copper substrate using two-step procedure including electrodeposition in the Watts bath and then thermal treatment in the presence of the AC-FAS. This case removed many practical limitations in the application of superhydrophobic surfaces. Fig. 10 shows the polarization curve of uncoated samples, samples electrodeposited by Ni, and SHS. As can be seen, the corrosion resistance of superhydrophobic surface is greater than that of the other ones. The microstructure of the fabricated superhydrophobic coating shows that, according to the Cassie-Baxter relationship, air can be trapped in surface lines, leading to the improved corrosion resistance of superhydrophobic surfaces.

Potentiodynamic polarizaiton curves measured in 3.5 wt% NaCl solution for the bare Cu substrate (Cu-I), electrodeposited Ni (Ni-I), and superhydrohobic surface (Ni-III) (Su and Yao, 2014).

Magnesium and its alloys are used extensively in the industry because of their good properties, but one of the limitations of using magnesium is their low corrosion resistance. It is indicated that, by applying the superhydrophobic coating on the surface of magnesium, it possesses very high resistance to corrosion. There are some reports about the fabrication of superhydrophobic coating on the surface of magnesium (Gao et al., 2014; Wang et al., 2010c), but most of the applied methods require special conditions and are expensive, as toxic substances should be used in many methods. Recently, the single-stage electrochemical method was introduced for applying hydrophobic coatings with high corrosion resistance on magnesium (Liu et al., 2015b). This method is simple, low-cost and nature-friendly and is believed to facilitate the operational applications of magnesium alloys.

Nickel is one of the engineering materials with desirable properties such as high corrosion resistance, hardness, and good magnetic properties, which can protect the copper substrate. Even more satisfactory properties can be obtained by combining these properties with superhydrophobic properties. Study on the fabrication of nickel superhydrophobic surfaces using a single-step electrodeposition without using the surface energy reducing materials and evaluation of the corrosion resistance of these coatings were done by Khorsand et al. (Esmailzadeh et al., 2015; Hashemzadeh et al., 2015; Khorsand et al., 2014; Khorsand et al., 2016 ). The corrosion resistance of coatings was studied by EIS and potentiodynamic polarization methods. The results showed the improvement in corrosion resistance of the substrate, caused by fabrication of SHS on the surface. In another study conducted by this group, effect of NH₄Cl on the microstructure and corrosion resistance of Ni coating fabricated by electrodeposition was studied (Hashemzadeh et al., 2015). The results indicated that NH₄Cl was significantly effective on the microstructure of the coating and as a result on the final corrosion resistance of created coating. Corrosion resistance of nickel-cobalt alloy superhydrophobic coating fabricated by electrodeposition was also investigated (Khorsand et al., 2016). These authors studied the long-term stability of these coatings and reported that improvement of corrosion resistance was affected by fabrication of superhydrophobic coating on the surface. Moreover, by increasing the time after fabrication of superhydrophobic coating, the corrosion resistance of the coating was improved by adsorption of a carbon layer on the surface.

Iron is one of the other engineering materials with numerous applications, but one of its disadvantages that caused lots of limitations in the industries is its low corrosion resistance (Cote et al., 2015; Fan et al., 2013). It has been shown that, fabrication of superhydrophobic coatings on the iron is one of the most important and applicable methods to improve its corrosion resistance. Many methods have been applied for fabrication the superhydrophobic coating on the substrate of iron (Gao et al., 2015a; Li et al., 2015b; Zhang et al., 2015c, 2015d ). However, most of the proposed methods suffer from many constraints such as time-consuming, being complicated, requiring special equipment as well as the raw materials and being expensive. Fabrication of superhydrophobic coating on the iron using a simple and low-cost approach is very effective. Black chrome is one of the coatings with very good corrosion resistance (Sheu et al., 2015), as its deposition on iron and applying superhydrophobic coating operation can be very useful. In this regard, Zhang et al. (Zhang et al., 2016a, 2016b, 2016c ) fabricated chromium coating on iron via electrodeposition method and then taking the stearic acid modification. They investigated the corrosion resistance of superhydrophobic coating by EIS and their results showed improved corrosion resistance by applying the superhydrophobic coating on the surface. Equivalent-circuits proposed by the electrochemical impedance curves for different samples are shown in Fig. 11. As shown in this figure, in the deposited and superhydrophobic-treated sample (Iron-BC-SA) with the most resistant to corrosion, air bubbles are trapped in the nanopores of the surface film that improved the corrosion resistance of the surface. Since the trapped air prevents the transformation between the electrolyte and the electrodes surface, electrons tend to pass through the limited points subject to the electrolyte. Thus, the effective conductive area is significantly decreased. In addition, due to the very high corrosion resistance of chromium layer, by applying a hydrophobic layer of stearic acid on a layer of chromium, electron transfer in this system is very difficult and corrosion resistance is significantly increased. The summary of other researches about corrosion resistance of superhydrophobic coating fabricated by electrochemical methods are represented in Table 1.

Electrical equivalent circuits for EIS of (a) Bare iron; (b) Iron-SA; (c) Iron-BC; (d) Iron-BC-SA (Zhang et al., 2016a, 2016b, 2016c).

Table 1 Summary of research about corrosion resistance of superhydrophobic coating fabricated by electrochemical methods.

Substrate	Method	Surface energy reducer agent	Contact angle	i_corr before treatment (A/cm²)	i_corr after treatment (A/cm²)	Corrosion protection efficiency (%)	Reference
Mild steel	Electrodeposition	Dodecyltrimethoxysilane	155	1.5 × 10⁻⁵	2.5 × 10⁻⁷	98	Zhou et al. (2016)
Mg	Electrodeposition	Perfluorocaprylic acid	160.2	26.4 × 10⁻⁶	7.61 × 10⁻⁶	71	Liu et al. (2016b, 2016c)
carbon steel	Electrodeposition	Palmitic acid	160.5	16.70 × 10⁻⁶	0.85 × 10⁻⁶	95	Fan et al. (2016b)
Iron	Electrodeposition	Ethanolic stearic acid	158.8	21.90 × 10⁻⁶	1.34 × 10⁻⁸	99.99	Zhang et al. (2016a, 2016b, 2016c)
Al	Electrodeposition	Stearic acid	160	16.06 × 10⁻⁶	10⁻⁸	99.99	Xu et al. (2016a)
Cu	Electrodeposition	Cerium myristate	161.5	7.096 × 10⁻⁶	4 × 10⁻⁷	94	Liu et al. (2015b)
Cu	Electrodeposition	Triethoxysilane	162	5.99 × 10⁻⁴	4.51 × 10⁻⁶	99.2	Su and Yao (2014)
Cu	Electrodeposition	–	155.7	3.2 × 10⁻⁶	5 × 10⁻⁹	99.99	Khorsand et al. (2014)
Cu	Electrodeposition	–	155	4.30 × 10⁻⁶	26 × 10⁻⁸	99.39	Esmailzadeh et al. (2015)
Cu	Electrodeposition	–	158	1.5 × 10⁻⁵	8 × 10⁻⁸	99.46	Khorsand et al. (2016)
Cu	Electrodeposition	1-dodecanethiol	154	9.33 × 10⁻⁶	10⁻⁸	99.89	Liu et al. (2016b, 2016c)
Cu	Electrodeposition	Myristic acid	160	7.84 × 10⁻⁶	4.08 × 10⁻⁷	95	Su et al. (2013)
Al	Electrodeposition	Myristic acid	162.1	7.16 × 10⁻⁸	8.76 × 10⁻¹¹	99.99	Zhang et al. (2015a)
Mg	Electrodeposition	Myristic acid	159.8	2.48 × 10⁻⁵	1.42 × 10⁻⁷	99.43	Liu and Kang (2014)
Al	Electrodeposition	Hexadecanoic acid	167.4	9.64 × 10⁻⁸	2.86 × 10⁻¹⁰	99.7	Zhang et al. (2016a, 2016b, 2016c)
Steel	Electrodeposition	Flour	157	7.27 × 10⁻⁶	4.12 × 10⁻⁶	43	Peng et al. (2016)

5.2

5.2 Chemical fabrication methods

Immersion in organic acids solutions is among the applicable methods which have been used to obtain a surface roughness as well as fabrication a surface with low surface energy. Hence, this method can be regarded among the one-step methods for creating superhydrophobic coatings (Wang et al., 2006b). Tetra decanoic acid is one of these organic acids that, because of its long fatty acid chains, can be noted as a nature-friendly materials for fabricating the superhydrophobic coatings (Richard et al., 2012). Coatings fabricated by this method can improve the corrosion resistance of the surface. Fig. 12 shows the polarization curves of magnesium uncoated samples after 2 h immersion in a solution of 3.5% NaCl in addition to the superhydrophobic surface fabricated on magnesium in different times. As shown, in the polarization curves, fabrication of superhydrophobic surface on magnesium surface significantly improves the corrosion resistance. (Zhao et al., 2014). This result was also reported in the other studies (Barkhudarov et al., 2008; Ishizaki and Saito, 2010).

Potentiodynamic curves of the untreated AZ31 magnesium alloy and superhydrophobic surface formed on magnesium alloy after immersion in 3.5 wt% NaCl aqueous solution for (a and e) 2, (b) 6, (c) 12 and (d) 24 h and enlarged the anodic curves (Zhao et al., 2014).

In another study, the corrosion resistance of the fabricated superhydrophobic coating via chemicals method and soaking in the solution of n-tetradecanoic acid and sea water on the copper substrate was studied (Liu et al., 2007a). Fig. 13 shows the potentiodynamic polarization curves of different samples. Obviously, the fabrication of the superhydrophobic coating on the surface reduces the corrosion current density and changes of corrosion potential toward more positive values. It can be seen that the current of the anodic branch was significantly decreased. In addition, it could be seen that the severe increase of the current in the anodic branch was removed in the presence of the superhydrophobic film, which confirms that the dissolution of copper and penetration of chlorine ion was severely restricted by the superhydrophobic film. Mechanism of corrosion resistance increase caused by the superhydrophobic film can be ascribe to air pocket phenomena in which, the superhydrophobic coating includes valleys and hills with entrapped gasses; therefore, chlorine ion hardly can reach the uncoated surface and hence corrosion resistance is increased.

Potentiodynamic polarization curves of the copper electrodes with and without the super-hydrophobic film for 1 day in sterile seawater at 2 mV s−1 (Liu et al., 2007a).

Fabrication of superhydrophobic coatings without organic modification operation has been the subject of many investigations (Liu et al., 2014c; Ning et al., 2011; Xu et al., 2011b, 2011c ). Cheng et al. (Cheng et al., 2015) fabricated the superhydrophobic coatings of Au-AlAu₄-Al₂O₃ on aluminum substrates without any organic modification operation and then examined the corrosion resistance of the created coating. Evaluation of corrosion resistance using potentiodynamic polarization method indicates the improved corrosion resistance of the superhydrophobic film formed on the surface. The mechanism of electrochemical corrosion of the created superhydrophobic coatings is shown schematically in Fig. 14. When the alloy is placed in the aqueous solution, corrosion starts by releasing the Al³⁺ ions, which lead to the formation of corrosion products in the form of Al(OH)₃ at the interface of the alloy and the substrate (Fig. 14a). Meanwhile, the cathodic reaction of hydrogen evolution ions occurs. As the chlorine ions penetrate to the alloy via tiny imperfections, they make small channels, which create pores on the surface (Fig. 14b). Then these pores join together, leading to the destroyed superhydrophobic surface of Au-AlAu₄-Al₂O₃ and hydrophobicity. Compared to the uncoated substrate, the substrate is removed more quickly by NaCl solution. Therefore, the SHS of Au-AlAu₄-Al₂O₃ provides better corrosion resistance to the substrate.

Schematic illustration of electrochemical corrosion mechanism of superhydrophobic surface in NaCl solution (Cheng et al., 2015).

Although the surface energy can be reduced by absorbing components with a low surface energy such as fluoroalkylsilanes (FAS) (Fadeev et al., 2002; McArthur et al., 2004), in many cases, FAS physically is adsorbed on the surface. Thus, it is expected that by chemical bonding of FAS to the surface, the stability of the formed superhydrophobic surface increases, leading to the improved corrosion resistance. Corrosion resistance of the superhydrophobic coatings was investigated by Ou et al. (Ou et al., 2012) by chemical adsorption of FAS on Ti-6Al-4V. The samples were first etched in HF solution, followed by performing the chemical adsorption of surface energy reducing agents on it. Samples were named as Ti-HF, Ti-HF/H₂O₂, Ti-HF-PFOTS, and Ti-HF/H₂O₂, where two samples of reducing agents were adsorbed on the surface and adsorption did not happen in the other two samples for which only chemical etching occurred. The exact mechanism of samples corrosion also can be attributed to air pocket which trapped in superhydrophobic surface. Due to the minute pore structures and large WCA, water can even push out of the pores of the SHS against the gravity force. Therefore, the surface is significantly protected.

Liu et al. (Liu et al., 2007b) synthesized the superhydrophobic coating on copper substrate using chemical etching by n-tetradecanoic acid (CH₃ [CH₂]₁₂COOH) and studied its corrosion resistance against seawater using EIS method. The Nyquist plot of uncoated and modified copper substrate is shown in Fig. 15. It could be seen that by deposition of n-tetradecanoic molecules on copper, charge transfer resistance increases, implying the increase in corrosion resistance. The Nyquist plot of modified copper suggests the presence of Warburg impedance which can be attributed to the cooperative binary structure at the superoleophobic surface.

Nyquist plot of Cu immersed in seawater for 1 day (25 °C) (Liu et al., 2007b).

Few studies have been conducted on fabrication of superhydrophobic surfaces resistant to corrosion on the magnesium alloys. Zhang et al. (Zhang et al., 2008a) created the superhydrophobic film of hierarchical micro/nanostructure on the PAO/Al substrate, which had a high level of corrosion resistance. In addition, Yin et al. (Yin et al., 2012b) fabricated the superhydrophobic coating on aluminum using chemical etching method as well as the modification operation, which also showed a good corrosion resistance.

Feng et al. (Feng et al., 2013) created the superhydrophobic surfaces on an aluminum substrate using an environmentally-friendly approach which showed a high corrosion resistance. To fabrication the SHS, after preparation of the surface, aluminum samples were placed in boiling water and finally samples were immersed in the solution of ethanol-water containing 10 mmol/l of stearic acid (STA) at 60 °C. Boiling water operation created a porous structure on the surface while in STA modification operation, hydrophobic alkyl chains were absorbed on the alloy. Therefore, it can be concluded that the fabrication of a superhydrophobic state depends on the geometry and surface energy. A schematic of the superhydrophobic coating formation is shown in Fig. 16.

The fabrication procedure of the superhydrophobic aluminum alloy surface (Feng et al., 2014).

The corrosion resistance test was conducted using polarization and indicated the improved corrosion protection because of the fabrication of a SHS. Fig. 17 shows the surface microstructure and STA layer at the interface of solid/air in addition to the micromodel of a water droplet in contact with the aluminum substrate. As shown in this schematic diagram, the surface of aluminum has a hierarchical structure in micro and nano-dimensions and also hydrophobic alkyl chains are adsorbed on the aluminum surface. Complex interfaces between liquids and solids cause the contact area between water drop and the solid surface become minimal and drop contact angle increase. By combining the chemical and physical effects, it can be realized that such a superhydrophobic surface can repel any hydrophilic molecules that move toward it. Thus, it can be concluded that the surface prevents the entrance of corrosive ions of the solution to an aluminum substrate and this leads to the improved corrosion resistance. The summary of other researches about corrosion resistance of superhydrophobic coatings fabricated by chemical methods are represented in Table 2.

Schematic illustration of a water droplet in contact with the superhydrophobic aluminum alloy surface (Feng et al., 2013).

Table 2 Summary of research about corrosion resistance of superhydrophobic coatings fabricated by chemical methods.

Substrate	Method	Surface energy reducer agent	Contact angle	i_corr before treatment (A/cm²)	i_corr after treatment (A/cm²)	Corrosion protection efficiency (%)	Reference
Mg	Immersion	Tetradecanoic acid	165	2.075 × 10⁻⁵	2.57 × 10⁻⁸	99.87	Zhao et al. (2014)
Mg	Etching	Dodecyl mercaptan	154	1.66 × 10⁻³	4.99 × 10⁻⁴	69.37	Feng et al. (2015)
Al	Immersion	HAuCl4	171	5.64 × 10⁻⁴	5.45 × 10⁻⁵	90.42	Cheng et al. (2015)
Al	Chemical etching	Flour	161.2	1.4 × 10⁻³	7.04 × 10⁻⁷	99.99	Yin et al. (2012a)
Al	Boiling water treatment	Stearic acid	155	1.25 × 10⁻⁴	1.65 × 10⁻⁵	86	Feng et al. (2013)
Al	Boiling water treatment	Stearic acid	154.1	7.26 × 10⁻⁴	5.01 × 10⁻⁵	93.11	Feng et al. (2014)
Ti	Etching	PFOTS	152.1	2.51 × 10⁻⁷	3.9 × 10⁻⁹	98.44	Ou et al. (2012)
Stainless steel	Etching	Silane	164.3	4.7 × 10⁻³	2.86 × 10⁻⁶	99.81	Latthe et al. (2015)

5.3

5.3 Sol-gel fabrication method

Alkylsilane is among the most important materials used for the preparation of superhydrophobic films for practical applications. The main reason for the widespread applications of this material is its high mechanical and chemical stability because of strong immobilization via siloxane bond (Rao et al., 2011). Alkylsilane sol-gel technique is an important single-step strategy to fabricate a superhydrophobic coating on engineering materials. This method allows to create rough structures and also reduce surface energy by hydrolysis and condensation of alkylsilane, simultaneously (Deng et al., 2011; Wen et al., 2011; Xue et al., 2009; Yang et al., 2010 ). Corrosion resistance and also stability of the silica-based coating created on the aluminum substrate in the corrosive solution of NaCl was studied by Liang et al. (Liang et al., 2014). In order to evaluate the corrosion resistance as well as stability of the coating, the coatings were immersed for different times in NaCl solution and polarization tests were applied on them (Fig. 18). Microscopic results showed slight surface change between 30 and 120 min of immersion. However, during a longer time range between 420 and 1440 min, major changes occurred on the surface morphology and the contact angle was decreased up to 138° at 1440 min of immersion, representing the destruction of hierarchical microstructure on the surface. Furthermore, the separation of hydrophobic agents occurred by increasing the immersion times. Polarization curves of different samples also show the reduction of corrosion resistance of coating as a result of increasing the immersion time. A noteworthy point in this curve is the more positive corrosion potential of coated and immersed samples at different times than the uncoated samples. Such difference can be attributed to the improved corrosion resistance of coating compared to uncoated sample. In general, the improved corrosion protection can be attributed to the simultaneous effect of superhydrophobic properties and also silica-based oxide films as a corrosion barrier.

Potentiodynamic polarization curves of (a) untreated aluminum substrate; and superhydrophobic surfaces formed on aluminum substrate after immersion in 3.5 wt% NaCl aqueous solution for (b) 30, (c)120, (d)420 and (e) 1440 min (Liang et al., 2014).

Superhydrophobic surfaces were also created by Fan et al. (Fan et al., 2012) via sol-gel process using the hydrolysis reaction between the vinyl-terminated trimethoxylsilane (VTMS) and wafer surfaces of copper substrate, where the surface roughness and surface energy were low. The stability test conducted in 3.5 wt% NaCl solution indicated that after 14 immersions, superhydrophobic state of this surface is maintained. However, after 14 days of immersion in a solution, it was found that the contact angle reached less than 150°, suggesting the decrease in superhydrophobic property of silica film. Corrosion resistance of superhydrophobic membranes in humidified atmosphere is new and ongoing investigations are being conducted on it. Wang et al. (Gao et al., 2014) studied the corrosion resistance of superhydrophobic membranes formed by sol-gel method and modified with hexadecyltrimethoxysilane (HDTMS), Tetraethyl orthosilicate (TEOS), trimethylethoxysilane (TMES) and methyltrimethoxysilane (MTMS) in a 3.5 wt% solution of NaCl and the moist air. The results showed the improved corrosion resistance by fabrication superhydrophobic surfaces on the surface of the uncoated sample. Fig. 19 shows a schematic of surface anti-corrosion mechanism created in corrosive environments. Trapped air on the surface can cause air protection shield, which significantly decreases the contact of corrosive ions with the steel substrate (She et al., 2012). Furthermore, it was concluded that in comparison with surface morphology, chemical composition of surface plays a more important role in resistance to corrosion in corrosive environment. Table 3 summarizes the results of studies conducted on the corrosion resistance of superhydrophobic surfaces created by the sol-gel methods.

Anti-corrosion mechanism of superhydrophobic membranes in corrosive solution medium (Gao et al., 2014).

Table 3 Summary of research about corrosion resistance of superhydrophobic coatings fabricated by sol-gel method.

Substrate	Method	Surface energy reducer agent	Contact angle	i_corr before treatment (A/cm²)	i_corr after treatment (A/cm²)	Corrosion protection efficiency (%)	Reference
Al	Sol-gel	–	154.9	4.08 × 10⁻⁷	2.79 × 10⁻⁹	99.31	Liang et al. (2014)
Steel	Sol-gel	Flour	151.5	7.68 × 10⁻³	3.44 × 10⁻⁵	99.55	Mo et al. (2015)

5.4

5.4 Spray coating fabrication method

Spray coating is a technique used for creating coatings in industrial dimensions. The main characteristic of this method is using inexpensive materials, simple manufacturing process, and its availability in commercial form (Wu et al., 2009). This method also can be used to fabrication of superhydrophobic substrates (Feng et al., 2004; Pan et al., 2008). Under such conditions, the increase surface roughness and reduction of surface energy is taken in one step by reacting alkanethiols salts and metals salts, which involve groups of high and low energy chains (Carotenuto et al., 2003). Superhydrophobic metal meshes were created via spraying method by Xu et al. (Xu et al., 2011d) through reducing the surface energy as well as increasing the surface roughness in one step by the reaction between the metals salt and alkanethiols. Stability and corrosion resistance of coated meshes were studied and the results showed that by creating a superhydrophobic coating on the surface, corrosion current density was decreased around two decades. As stated earlier, one of the major problems that cause functional limitations of superhydrophobic coatings is the mechanical stability of the coatings. Therefore, fabrication of coatings with high mechanical durability, and at the same time superhydrophobicity, is one of the challenges we face todays. In order to overcome this problem incorporating nanoparticles and sticks in coatings were suggested. In this regard, polydimethylsiloxane (PDMS) resin is frequently used for its high mechanical stability, low surface energy, and superhydrophobic properties (Chakrabarty et al., 2012; Thanawala and Chaudhury, 2000). Zhang et al. (Zhang et al., 2016g) used the spraying method to create coatings with high corrosion resistance and high mechanical stability. In this study, PDMS and inorganic nanoparticles of fluorinated alkyl silane functionalized silica were used in coatings. The results of the corrosion resistance evaluation by electrochemical impedance spectroscopy and polarization tests showed that the fabrication of superhydrophobic coating caused a 315 times reduction in corrosion current density. The researchers considered the improved corrosion protection of coating because of two reasons: the effect of capillary forces and the impact of air pockets and barrier layer (Fig. 20). Under the superhydrophobic condition, surface has a hierarchical structure, as such structure can entrap the air between the created intervals, reduce the real surface between the corrosive liquid and the substrate, and improve the corrosion resistance. As noted above, stability of hydrophobic coating under extreme conditions is one of the big challenges of coatings. Polysulfone (PSU) is one of the materials used to create superhydrophobic coatings because of its unique properties such as excellent thermal stability, excellent mechanical properties and chemical inertness (Yue et al., 2013). Nevertheless, brittleness is one of the main disadvantages of this material which limits its application for fabrication of abrasion resistant coatings. Polymers with excellent ductility can be used to overcome this problem. PVDF polymer is used for removing the PSU limitations (Stoiljkovic and Agarwal, 2008). PVDF also has a very low surface energy and is used to reduce the surface energy of materials. It is also used for fabrication of hierarchical microstructure in MMT covers. In the same way, composite and superhydrophobic coatings of PSU/PVDF/MMT/PDMS which was resistant to abrasion and corrosion were introduced by Wang et al. (Zhang et al., 2016f) by a combination of chemical modification and simple spray methods. The prepared superhydrophobic coating showed excellent properties. Besides, the hierarchical structure created by incorporation of MMT to coating improved the mechanical properties of the coating as 14.3%. Angular curve of the created coating and immersion in different pH values are shown in Fig. 21. As it could be seen, in different acidic or basic conditions not much changes were observed in the coating contact angle; implying that the corrosion resistance of coating in different acidic and alkaline conditions was perfect.

Schematic illustration of the capillary effect (a) and coating-corrosion liquid interfaces (b) (Zhang et al., 2016f).

The relationships between pH and WCA on the PSU/PVDF/MMT–PDMS composite coating (Zhang et al., 2016f).

Due to the potential applications of superhydrophobic surfaces, fabrication of colorful superhydrophobic surfaces was always of great importance in academic and industrial sectors. But up to now, fabrication of colorful SHS has rarely occurred due to the difficulty in changing the color and appearance of coatings. Recently researchers aimed to create colorful super-hydrophobic surfaces (Ge et al., 2014; Ishizaki and Sakamoto, 2011; Ogihara et al., 2011; Soler et al., 2011 ). Colorful superhydrophobic coatings were created by Wu et al. (Li et al., 2015a) using a simple and single step procedure of spray-coating by spraying stearate particle ethanol suspensions on stainless steel in order to study the corrosion resistance of the created coatings. Test results showed that the corrosion resistance of coating has been two or three times better than that of uncoated substrate. Furthermore, results of long-term immersion showed that the created coating has a good long-term sustainability. In addition, results of the electrochemical impedance curves showed that by increasing the immersion time, slight changes occurred in diameter of capacitive loop, which in turn represents the high stability of the coatings. Table 4 summarizes the results of studies on the corrosion resistance of superhydrophobic surfaces created by the spray methods.

Table 4 Summary of research about corrosion resistance of superhydrophobic coatings fabricated by spraying method.

Substrate	Method	Surface energy reducer agent	Contact angle	i_corr before treatment (A/cm²)	i_corr after treatment (A/cm²)	Corrosion protection efficiency (%)	Reference
Cu	Spraying	n-octadecanethiol	161	3.89 × 10⁻⁷	8.66 × 10⁻⁹	97.77	Xu et al. (2011d)
Cu	Spraying	Silane	156	5.75 × 10⁻⁵	1.82 × 10⁻⁷	99.68	Zhang et al. (2016g)
Al	Spraying	PVDF	159	10^−0.9 × 10⁻⁶	10^−3.6 × 10⁻⁶	29	Zhang et al. (2016f)
Al	Spraying	–	156	2.41 × 10⁻⁶	2.42 × 10⁻⁸	98.99	Cao et al. (2009)
Al	Spraying	Stearate particle	162.1	2.41 × 10⁻⁶	3.27 × 10⁻⁸	98.64	Li et al. (2015b)

5.5

5.5 Hydrothermal synthesis fabrication method

Regarding its high efficacy in fabrication of microstructures, hydrothermal synthesis method is one of the best options for creating superhydrophobic surfaces (Guo et al., 2012; Wang et al., 2010a). Zhang et al. (Zhang et al., 2015b) applied a superhydrophobic coating on magnesium substrate to improve its corrosion resistance using a combination of simple hydrothermal treatment and modification methods by stearic acid. Based on this study, initially using the hydrothermal process, a hierarchical structured oxide layer was deposited on a substrate of magnesium hydroxide, which simplified the operation by stearic acid. The corrosion resistance of coatings and their long-term stability were also investigated. Results of the corrosion resistance studies showed that the highest corrosion resistance belongs to the coating created by hydrothermal operation and then treated by corrective actions with stearic acid. In order study the long-term sustainability, various samples were immersed in 3.5 wt% NaCl solution for 120 h. Fig. 22 shows images of the immersion of samples. As could be seen, a high local corrosion rate occurred on the surface of uncoated sample, while in the case of the hydrothermal treated sample, local corrosion of the surface was reduced; implying that the hydrothermal treatment could improve the long-term stability of the samples. But it is also observed that the corrosion was lowered on the surface of superhydrophobic coated sample, suggesting that the superhydrophobic operations have effectively improved the long-term stability.

Photographs of various samples after 120 h immersion in 3.5 wt% NaCl solution: (a) bare AZ31 substrate, (b) the hydrothermal treated sample, and (c) the superhydrophobic sample (Zhang et al., 2015b).

Magnesium is one the low-density metals which has been a great interest in many industries. One way to improve the corrosion resistance of this metal is to create LDHs layer on it (Wu et al., 2014a; Zheludkevich et al., 2010). Among the existing methods to fabricate the layer, the hydrothermal synthesis has a high capacity of flexibility due to the control of surface morphology. Zhou et al. (Zhou et al., 2015) created a superhydrophobic film of zinc-aluminum layered double hydroxides (Zn-Al LDHs) on the substrate of magnesium using a simple hydrothermal crystallization method followed by chemical modification, and then investigate the corrosion resistance of created layer by polarization method. Fig. 23 shows the polarization curves of substrate, hydrothermal-treated, and superhydrophobic samples. Accordingly, the superhydrophobic samples represent lowest corrosion current density, and most positive corrosion potential, indicating the highest corrosion resistance.

Potentiodynamic polarization curves of the bare Mg alloy substrate, Zn–Al LDHs coated Mg alloy and superhydrophobic Mg alloy surface. (Zhou et al., 2015).

Oxide films formed on the metals act as the barrier layer to prevent corrosion. Although techniques such as plasma electrolytic oxidation are used to fabricate the layer (Aliofkhazraei et al., 2010; Seyfoori et al., 2013), they involve high complexities. Instead, using a simple hydrothermal method, we can create a hydride or oxide layer on the light metals with rough microstructure. For improving the corrosion resistance as well as creating the superhydrophobic condition, chemical treatment can be used after the hydrothermal treatment to reduce the surface energy. Ou et al. (Ou et al., 2013b) used hydrothermal treatment to form the oxide or hydroxide barrier layer on the light alloy substrates. Then, for creating superhydrophobic conditions, they decreased the released surface energy by means of surface energy reducing materials and examined the corrosion resistance behavior of the coating and its stability. Corrosion resistance studies showed the improved resistance to corrosion by creating a superhydrophobic coating. To evaluate the long-term sustainability, the created coatings were immersed in sodium chloride solution for different durations. It was observed that by increasing the duration of immersion, the contact angle varied from more than 150° to less than 10° and SA increased from less than 10° to 90°. Thus, it can be concluded that the superhydrophobic state was destructed by increasing the duration of immersion. In this study, two methods were used to create superhydrophobic coatings including hydrothermal treatment and fabrication of superhydrophobic coating (HT-SHS) and chemical etching followed by the fabrication of superhydrophobic coating (CE-SHS). The results showed that the coating created by HT-SHS method had a longer durability than other coatings. The reason for such behavior is the generation of an oxide and hydroxide layer on the metals surface acted as barrier layer. In addition, the layer of oxide and hydroxide increased the active sites of hydroxyl groups on the surface, which improved the adsorption of perfluoroalkylsilane on the surface.

5.6

5.6 Electrospinning fabrication method

Electrospinning is a very powerful technique to synthesize fine fibers in the view of many scholars. This technique is useful to generate the required roughness for fabricating the superhydrophobic mode. Surface roughness and surface microstructure of the fabricated coating can be controlled by many parameters such as concentrations of polymer or polymer type, electrospinning parameters such as applied potential and flow rate (Acatay et al., 2004; Peng et al., 2005). As noted before, PVDF has a low surface energy and it can be used to reduce the surface energy of materials. In many investigations, nanomaterials such as zirconia, alumina, silica, titania, and ZnO were mixed with PVDF (Hashim et al., 2011; Mohamed et al., 2014). Radwan et al. (Radwan et al., 2015) created the PVDF-ZnO coating on aluminum using the electrospinning technique for corrosion protection. The results of corrosion resistance survey showed that polarization resistance of Al-PVDF-ZnO coating was more than Al-PVDF alone. The primary cause for the improved corrosion resistance by incorporating ZnO nanoparticles into the coating is the formed pores on the surface. These pores prevent the diffusion of corrosive ions into the nanocomposite coating, because of the existence of trapped air. When there is only Al-PVDF in the coating, large pores are created; which cannot prevent the penetration of corrosive ions to the surface of the coating. Images of Al-PVDF-ZnO and Al-PVDF samples after polarization tests are shown in Fig. 24. Accordingly, at the surface of the sample whit out ZnO nanoparticles, there are many corrosion pores, while on the surface of the sample including ZnO nanoparticles the coating has fully covered the surface and no significant corrosion occurred.

SEM micrographs for (A) pure PVDF and (B) PVDF–ZnO composite after Tafel polarization in 3.5 wt% NaCl using a scan rate of 0.167 mV s−1 (Radwan et al., 2015).

Superhydrophobic coatings have been successfully fabricated by Grignard et al. (Grignard et al., 2010) on aluminum with excellent corrosion resistance using the electrospinning of new solution of the fluorinated diblock copolymer. In this study, the accelerated acetic acid salt spray test was used for studying the corrosion resistance of created coating. After placement of various samples for 100 and 200 h in corrosive environments, their corrosion resistance was monitored. Images of the samples after salt spray tests are shown in Fig. 25. As could be seen in the images, the highest corrosion resistance was for the coating with higher thickness.

Corrosion test of aluminum plate covered by pure P(FDA-co-AA)-b-PAN diblock copolymer exposed to acetic acid salt spray test (5% NaCl, 1–3% HAc, pH 3.1–3.3, 35 (1C): (A) Neat aluminum plate. (B) Surface coated by a coating of 3.1 (2.5 μm thickness, after exposure for 200 h, black spots = corrosion. (C) Surface coated by a coating of 23.2 (8.2 μm thickness after exposure for 200 h (Grignard et al., 2010).

5.7

5.7 Laser operations fabrication method

Laser marking is one of the simple, straightforward affordable operations with many applications (Tang et al., 2015). By adjusting the operating parameters such as laser processing textures spacing and laser scanning speed, it can be precisely control the surface morphology. Tang et al. (Tang et al., 2016) created the superhydrophobic coating on an aluminum substrate using laser marking method with an array of micro-orifices and evaluated the corrosion resistance of created coating in corrosive environments such as seawater and acidic and alkaline solutions. In addition, the mechanical and chemical stability of created surface were also studied. The results of the corrosion resistance evaluation showed that the corrosion resistance of the superhydrophobic coating was about 1.7% of the uncoated substrate. Moreover, variation of the contact angle with pH values in immersion environment showed that no considerable change occurred in contact angle, implying the significant corrosion resistant of the created coating. The mechanism of corrosion resistance of the superhydrophobic coating can be explained based on Fig. 26. When the laser-treated sample is immersed in a modification solution, perfluorosilane self-assembled monolayers could be created on the surface. Also, because of the high polarity and the electron withdrawing effect of fluorine atoms, C-F bond has a very strong chemical inertness. Thus, the created perfluorosilane has very low surface energy and can prevent the electron transmission which passes the corrosive solution. In addition, based on the conducted calculations, about 92% of the created rough surface is covered by the air and just 8% is in contact with a corrosive environment that also improves the corrosion resistance of the surface.

Schematic illustration of effect of the hydrophobic modification and specific roughness structure of the surface to the improvement of corrosion resistance (Tang et al., 2016).

5.8

5.8 Methods based on anodic oxidation

5.8.1

5.8.1 PEO and MAO

Through the methods of creating oxide layer such as plasma electrolytic oxidation (Darband et al., 2017; Farhadi et al., 2017b; Farhadi, 2014; Gnedenkov et al., 2011 ) method and anodizing (Liu et al., 2013), it is possible to create a rough surface, with at the micro/nanoscale roughened. Superhydrophobic surfaces can be made by reducing the surface energy of the coatings.

Cui et al. (Cui et al., 2015) created a superhydrophobic coating on the surface of AZ31 alloy to improve the corrosion resistance of magnesium created by MAO two-step procedure. In this research, in order to create a hydrophobic surface, MAO coated samples were immersed at different times in the stearic acid solution, where the surface contact angle was increased by increasing the immersion time. The maximum angle was 151.1° obtained by immersion for 10 h. Corrosion resistance was studied by potentiodynamic polarization curves (PDP), EIS, and long-term immersion test, which showed that fabrication of superhydrophobic surface improved the corrosion resistance of MAO coatings and therefore the AZ31 alloy. This mechanism was proposed for the fabrication of a hydrophobic surface (Fig. 27). As shown in this figure, MAO method was applied to create a microporous surface. The outer layer was porous and hydrophilic, while the inner layer was dense. By immersion of the MAO-treated sample in ethanol stearic acid solution, due to the low surface energy of the liquid, it penetrated through porous layers, which is associated with self-assembly process (b–c). The porous surface of the layer was coated by oxide and hydroxide to promote a chemical reaction of stearic acid as a monolayer on the surface of MAO coating. The stearic acid reaction causes the formation of symmetric and asymmetric sediments and the sediments remain in the pores of a single weak layer, which consequently increases the capacitance 2 of MAO coating. Results presented in Fig. 27c show the formation of a hydrophobic layer on the MAO coating, where both single-layers and sediments resulted in the sealing of coating, and as a result improved the corrosion resistance. It is well known that the cathodic reaction of hydrogen gas occurs at the cathodic polarization curve while the anodic reaction is related to the dissolution of coating/metal. As shown in Fig. 28, the cathodic polarization for samples with MAO coating and hydrophobic samples was similar to the uncoated alloy. The cathodic reaction of the substrate was less affected by MAO coating and the hydrophobic modification. However, evidence suggests that the polarization curve of coated alloy has the passive area. Results showed that the corrosion resistance of MAO coatings is significantly increased after modification by stearic acid. It also means that the hydrophobicity created by bonding of the carboxyl group of stearic acid on the surface can effectively reduce the surface contact with the corrosive solution, which will further improve the corrosion resistance.

Schematic representation of the formation of a H-MAO coating on AZ31 Mg alloy: (a) formation of a MAO coating, (b) hydrophobic modification of the MAO coating, and (c) the formation of a H-MAO coating by increasing the micro-pores (Cui et al., 2015).

PDP curves of AZ31 Mg alloy in an uncoated state, and with MAO coatings modified for different times in a 3.5 wt% NaCl aqueous solution (Cui et al., 2015).

Gnedenkov et al. (Egorkin et al., 2016; Egorkin et al., 2015) created the superhydrophobic coatings on aluminum alloys by two-stage PEO method. For generating the hydrophobic coating, first PEO method was used for creating a rough and porous surface and then the coated samples were immersed in a solution containing ethanol and a hydrophobic agent. For creating the chemically active surface, samples were treated in two different ways including washing by ethanol and irradiated by UV in the presence of the ozone plasma and then their effect on corrosion resistance were also examined. Corrosion testing results showed that the superhydrophobic coating improved the corrosion resistance of the alloy. Furthermore, the hydrophobic coating had the highest contact angle and maximum corrosion resistance under UV radiation.

Guo et al. (Guo et al., 2009) fabricated the hydrophobic nanocomposite coating on magnesium alloy using single-stage PEO treatment. In this regard, Polytetrafluoroethylene (PTFE) was used as nanoparticle in the structure of hydrophobic nanocomposite nanoparticles because of its hydrophobic properties, chemical stability, and high corrosion resistance in the coating structure. The size of the drop contact angle obtained for the PEO nanocomposite coating was 101°. Corrosion resistance evaluation showed that the PEO nanocomposite coating had lower corrosion current density and more positive corrosion potential than pure PEO coating, indicating the improved corrosion properties.

Jiang et al. (Jiang et al., 2015) fabricated a superhydrophobic coating on Ti-6Al-4V alloy using two-stage MAO method. To obtain a superhydrophobic coating, the MAO coated alloy was immersed in an organic solution containing 2H-perfluorooctyl-trichlorosilane (PFOTS) for 12 h. The contact angle of the superhydrophobic coating of MAO was 153°. The results of corrosion resistance studies showed that the superhydrophobic coatings had a more positive corrosion potential and lower corrosion current density than the specific alloy and MAO coating, which causes higher corrosion resistance as shown in Fig. 29. The increase in corrosion resistance due to the loss of contact surface of corrosion solution with the superhydrophobic surface is justified because of the existence of air in the pores and surface roughness.

Potentiodynamic polarization curves of Ti-6Al-4 V, MAO and MAO + TFOS samples in Hank's solution (Jiang et al., 2015).

Wang et al. (Wang et al., 2012b) created a superhydrophobic coating on the Mn-Li alloy using a two-step MAO-sol-gel method. MAO layer was used as the middle layer of superhydrophobic coatings because of very rough surface, high corrosion resistance, as well as high cohesion to the outer layer or the hydrophobic layer. Also, a layer of silica, as a hydrophobic layer film was coated on MAO layer by sol-gel method. According to Fig. 30, corrosion current density of superhydrophobic coating has the lowest value for the uncoated alloy and the alloy coated by MAO. In addition, it should be noted that the superhydrophobic silica film showed a better performance than pure silica provides in the case of corrosion protection. Such a higher performance means that, regarding the linked the presence of functional groups methyl on its surface, superhydrophobic coatings can effectively reduce the contact area and thus increase the corrosion resistance.

Potentiodynamic polarization curves of various samples in 3.5 wt% NaCl solution (Wang et al., 2012b).

5.8.2

5.8.2 Anodizing method

Anodizing is another electrochemical method that can be used to fabricate rough surface to obtaining superhydrophobic surface. He et al. (He et al., 2009) fabricated a superhydrophobic coating on aluminum by two-stage method of anodizing-chemical approach. Once, the first anodizing operation was performed on metal, and then superhydrophobic surface was created on the metal using chemical methods. The contact angle of droplet on surface was reported to be 154°. Also, the corrosion resistance of coatings was investigated. The results showed that corrosion resistance was significantly increased due to the reduced contact surface of metal and seawater solution.

Yin et al. (Yin et al., 2011) proposed a simple and efficient method for fabrication industrial scale superhydrophobic coatings on aluminum alloy. Through this procedure, first, the metal was coated by the anodizing method and then the superhydrophobic surface was generated on this layer via chemical etching. Corrosion resistance of superhydrophobic coatings was evaluated as the corrosion resistance was increased. Also, the stability of the superhydrophobic coatings was investigated, for which the results showed that the coating had a chemical stability in sea water solution.

Superhydrophobic coatings were created on aluminum via two-stage anodizing-chemical approaches, where the corrosion resistance increased. Chemical and mechanical stability and weathering superhydrophobic coatings were also examined. The results showed that superhydrophobic coatings were almost stable in acidic and alkaline environments and the coating possessing mechanical stability has been tested by sandblasts system. Results for sustainability erosion (for 7 days) superhydrophobic coating does not cover significant changes in the contact angle is stable erosion. Results for erosion sustainability (for 7 days) of superhydrophobic coating did not show any significant change in contact angle while the coating showed high erosion stability (Zheng et al., 2016).

The superslippery coating was fabricated on aluminum alloy using anodizing and immersion methods, which improved the corrosion resistance of the aluminum alloy. The effect of the anodizing process on the corrosion resistance was also evaluated, so the corrosion resistance of these super-slippery coating fabricated on the surface of pure aluminum and super-slippery coating fabricated on the surface of anodized aluminum were compared (EIS). As shown in Fig. 31, the results showed that the coating fabricated on the anodized surface had higher corrosion resistance than the one fabricated on pure aluminum, which is not due to lack of porous surface on the non-anodized aluminum. Porous surface creates the super-slippery stable coating without pores and gaps; thus, it improves the resistance to corrosion (Song et al., 2015). Table 5 shows a summary of study results on the corrosion resistance of superhydrophobic surfaces created by the anodic oxidation-based methods.

Nyquist plots of Co3O4 grown AAO and pure aluminum super slippery surfaces after immersion for 16 h in 3.5% NaCl solution (Song et al., 2015).

Table 5 Summary of research about corrosion resistance of superhydrophobic coating fabricated by anodic oxidation based methods.

Substrate	Method	Surface energy reducer agent	Contact angle	i_corr before treatment (A/cm²)	icor after treatment (A/cm²)	Corrosion protection efficiency (%)	Reference
Titanium	PEO	Methoxy-silane	165.8	$1.4 \times 10^{- 7}$	$1.4 \times 10^{- 9}$	98.60	Gnedenkov et al. (2011)
Mg-Li	MAO	ATP		$1.37 \times 10^{- 4}$	$5.6 \times 10^{- 7}$	99.60	Hou and Kang (2013)
Mg–Mn–Ce	PEO	Methoxy-silane	166	$6.6 \times 10^{- 6}$	$1.5 \times 10^{- 9}$	99.97	Kang et al. (2011)
Aluminum	Anodizing	Stearic acid	160	$2 \times 10^{- 7}$	$88 \times 10^{- 9}$	95.60	Huang et al. (2016)
AZ31 Mg alloy	MAO	Stearic acid	151	$16 \times 10^{- 7}$	$14 \times 10^{- 9}$	99.91	Cui et al. (2015)
Aluminum	PEO	Methoxy-silane	157	$6.1 \times 10^{- 7}$	$4.8 \times 10^{- 12}$	99.99	Egorkin et al. (2015)
Titanium	PEO	N,N,N-trimethyl-1-silane	165	$1.4 \times 10^{- 7}$	$1.4 \times 10^{- 9}$	–	Gnedenkov et al. (2014)
Magnesium alloy			166	$6.6 \times 10^{- 6}$	$1.5 \times 10^{- 9}$
Low-carbon steel			161	$2.1 \times 10^{- 9}$	$3.3 \times 10^{- 9}$
Magnesium	PEO	Polytetrafluoroethylene	101	$2.4 \times 10^{- 6}$	$2.1 \times 10^{- 7}$	91.25	Guo et al. (2009)
Ti-6Al-4 V	MAO	PFOTS	153.3	$2.2 \times 10^{- 7}$	$1.4 \times 10^{- 8}$	93.63	Jiang et al. (2015)
Mg–Nd–Zn–Zr	MAO	Tetraethoxysilane &methyltriethoxysilane	151	$2.2 \times 10^{- 5}$	$2.6 \times 10^{- 8}$	99.88	Wang et al. (2012b)
Aluminum	Anodizing	Fluorinated silane	163	$5.6 \times 10^{- 6}$	$1.5 \times 10^{- 8}$	99.73	Zhang et al. (2015c, 2015d)
Aluminum	Anodizing	Myristic acid	155.2	$3 \times 10^{- 7}$	$1.52 \times 10^{- 9}$	99.49	Zheng et al. (2016)
Aluminum alloy	Anodizing	Myristic acid	155.6	$2.7 \times 10^{- 7}$	$9.9 \times 10^{- 11}$	99.63	Zheng et al. (2015)
Mg-Li-Ca alloy	PEO	Stearic acid	155.5	4.23 × 10⁻⁵	5.36 × 10⁻⁸	99.2	Zhao et al. (2017)

5.9

5.9 Plasma techniques

In the recent years, some works have been reported using plasma techniques to approach superhydrophobic surfaces. One of the beneficial factors in this technique is the ability of utilizing different gases for plasma treatments. Yung et al. found that the use of $O_{2}$ and/or ${CF}_{4}$ plasma on vertically aligned carbon nanotubes (VACNTs) could lead to obtain highly efficient superhydrophobic surfaces by changing the morphology of VACNTs (Yung et al., 2018). Also, usage of Argon and Oxygen gases in plasma treatment on polytetrafluoroethylene (PTFE) was investigated. They achieved a great change in contact angle (up to 178°) via a single step treatment of the as-mentioned substrate (Ryu et al., 2017). In addition, suspension plasma spraying (SPS) in another branch of plasma techniques used to approach superhydrophobic surfaces for the future applications in the engineering field. Sharifi et al. (Sharifi et al., 2017), prepared surfaces with significant superhydrophobicity by controlling of coating parameters and obtaining dual-scale surface textured coatings.

5.10

5.10 Other fabrication methods

many other methods have been used to create superhydrophobic surfaces and their corrosion resistance was also investigated. A summary of all of these methods, as well as the improved corrosion resistance of the substrate because of the fabrication of superhydrophobic layer, is presented in Table 6.

Table 6 Summary of research about corrosion resistance of superhydrophobic coating fabricated by other methods.

Substrate	Method	Surface energy reducer agent	Contact angle	i_corr before treatment (A/cm²)	i_corr after treatment (A/cm²)	Corrosion protection efficiency (%)	Reference
Mg	Phase separation	–	155	1.73 × 10⁻⁵	9.17 × 10⁻⁹	99.46	Yang et al. (2016)
Cu	Dip coating	STA	162.3	6.7 × 10⁻⁵	6.2 × 10⁻⁶	90.74	Qing et al. (2015)
Cu	Dip coating	PVDF	160.1	6.7 × 10⁻⁵	1.1 × 10⁻⁶	98.35	Qing et al. (2016)
Cu	Polymerisation	HFBA	159	34 × 10⁻⁶	1.61 × 10⁻⁶	95.26	Yuan et al. (2011)
Cu	Etching and calcination	Stearic acid ethanol solution	157.6	4.31 × 10⁻⁶	2.35 × 10⁻⁸	98.90	Liu et al. (2016a)
Cu	Electroless and electro deposition		153.2	10.37 × 10⁻⁶	0.85 × 10⁻⁶	91.80	Hu et al. (2015)
Stainless steel 316 l	Flame spraying	PU	151	2.21 × 10–3	1.87 × 10–4	91.53	Chen et al. (2014)
Stainless steel	Etching and oxidation	–	158.2	3.35 × 10⁻⁷	1.08 × 10⁻⁷	67.76	Park and Hwang (2016)
Al	Spin coating	–	161.2	0.19 × 10⁻⁶	0.008 × 10⁻⁶	95.87	Momen and Farzaneh (2014)
Al	Spin coating	Graphene-E	153.7	7.19 × 10⁻⁴	2.54 × 10⁻⁷	99.64	Liu et al. (2014c)
Al	Etching and spraying	PVDF	164	10⁻⁶	10⁻⁸	99	Wang et al. (2015)
Al	Anodization	Myristic acid	155.2	3.06 × 10⁻⁷	1.52 × 10⁻¹⁰	99.95	Zheng et al. (2016)
Al	Boiling water treatment	Stearic acid	156.6	1.54 × 10⁻⁵	2 × 10⁻⁷	98.70	Feng et al. (2016)
Al	Chemical etching and anodization	FDTS	170	1.65 × 10⁻⁴	2.36 × 10⁻⁸	99.99	Wang et al. (2016)
Al	Chemical etching and anodization	PTES	156	6.33 × 10⁻⁶	5.71 × 10⁻¹⁰	99.99	Wu et al. (2016)
Mg	Electrochemical machining process	FAS	165.2	9.96 × 10⁻⁵	9.68 × 10⁻⁸	99.90	Xu et al. (2011b, 2011c)
Cu	Self-assembly	PFDTS	152.5	180 × 10⁻⁶	5.3 × 10⁻⁶	97.05	Ou et al. (2013a)
Mg	Microwave plasma-enhanced chemical vapor deposition	–	150	9.25 × 10⁻⁵	7.41 × 10⁻⁸	99.91	Ishizaki et al. (2010)
Al	Successive thermal treatment	–	169	1.06 × 10⁻⁴	1.84 × 10⁻⁶	98.26	Cheng et al. (2015)
Zn	Immersion process	PFTS	151	1.09 × 10⁻⁵	1.62 × 10⁻⁷	98.51	Liu et al. (2009a)
Zn	Electroless deposition	DDT	152	4.38 × 10⁻⁴	1.6 × 10⁻⁴	63.47	Shi et al. (2014)
Zn	Etching in hydrochloric acid, electrodeposition of ZnO coatings, thermal annealing	–	170	1.66 × 10⁻⁴	7.24 × 10⁻⁵	56.38	Zhang et al. (2016a, 2016b, 2016c)
Carbon steel	Electric corrosion	Stearic acid ethanol solution	152	10⁻⁵	1.25 × 10⁻⁷	98.75	Sun et al. (2016)
Brass	Etching and heat treatment	Stearic acid ethanol solution	153.6	9.55 × 10⁻⁷	5.40 × 10⁻⁹	99.43	Jie et al. (2016)
Titanium	Chemical etching	Fluoroalkylsilane	160	1.46 × 10–7	1.69 × 10⁻¹⁰	99.88	Lin et al. (2016)
Mg	Co-precipitation method and hydrothermal	Stearic acid	153.5	4.7 × 10⁻⁵	3.4 × 10⁻¹⁰	99.99	Zhang et al. (2016d)

6 Chemical stability

6.1

6.1 The necessity of chemical stability investigation

A very influential parameter in evaluation of corrosion resistance of superhydrophobic films is determination of their chemical stability under various working conditions and solutions. As chemical stability is a crucial variable in selection of materials for duty in a specific environment, the process of measurement and evaluation itself becomes considerably important.

6.2

6.2 Chemical stability fading mechanisms

Considering the fact that fabrication of superhydrophobic films requires two essential conditions which are surface roughness and low surface energy, it may be deduced that a film may lose its chemical stability due to following mechanisms:

6.2.1

6.2.1 Loss of roughness

After being exposed to the chemical medium, the film may undergo a chemical process. Hence, the rough materials that constitute the film are dissolved according to their inherent properties. The film, therefore, loses its primary rough morphology over time (Fig. 32) and contact angle of droplet reduces gradually. It is even possible that the film becomes hydrophilic (Cai et al., 2015; Cui et al., 2017; Farhadi et al., 2017a; Guo et al. (2015b)).

Fading of surface roughness as a result of exposure to a corrosive medium.

6.2.2

6.2.2 Dissolution of surface layer

Another proposed mechanism for chemical instability of a film after immersion in the corrosive medium is removal or alteration of the chemical composition of surface layer with minimum surface tension due to chemical reaction with the surrounding corrosive medium (Fig. 33). Thickness of the surface layer which is responsible for low surface energy and superhydrophobic properties reduces as the layer reacts with the solution. In another scenario, chemical composition of functional groups of the surfactant changes due to various processes leading to a gradual increase in surface energy and fading of superhydrophobic properties (Farhadi et al., 2017a; Guo et al. (2015a); Heinonen et al., 2014; Ishizaki et al., 2010; Zhao et al., 2017 ).

Chemical instability of surface layer due to (a) dissolution of layer and (b) change of layer chemical composition.

6.3

6.3 Chemical stability evaluation

There are many methods for evaluation the chemical stability of superhydrophobic coatings. In the following sections, we will review recent studies on superhydrophobic films based on the methods used for evaluation of chemical stability.

6.3.1

6.3.1 Contact angle versus pH variations

As it was mentioned earlier, it is highly frequent in experimental works to evaluate chemical stability by achieving contact angle versus pH plots. Chemical stability of a superhydrophobic film is readily estimated with this method. It should be noted that while investigating pH, the working environment of a film is given attention rather than its lifetime. An example for such studies is formation of thin superhydrophobic films through chemical electrodeposition from reinforced vapor phase with microwave plasma (MPECVD). Ishizaki et al. (Ishizaki et al., 2010) deposited films on a magnesium substrate and immersed them in different media. It was reported that films were deteriorated in alkaline solutions and almost became hydrophobic. It was revealed that SiO_x which is the functional group responsible for superhydrophobic properties was dissolved at pH ranges above 10 and consequently the film's stability was lost. In addition, contact angle also decreased, not as intensely as alkaline solutions though, in acidic solutions; hence, it may be deduced that the best stability may be expected in neutral solutions. Yang et al. (Yang et al. (2015)) investigated formation of self-repairing super hydrophobic films on Mg substrates through immersion in special baths designed for deposition of self-repairing coatings. It was shown that contact angle reduced with increase in acidity; yet, it remained above 150° and the medium did not affect stability of films.

Li et al. (Zhao et al., 2017) fabricated superhydrophobic properties on steel pipelines through deposition of Cu-Zn films with rough dandelion-like in a two-step procedure including electroplating and chemical oxidation. The stability of such films was reported excellent in all environments except harsh alkaline solutions. This was due to removal of the acid molecules adsorbed on surface by the alkaline medium. Carbon and fluorine faded gradually indicating removal of the acid layer.

Another application of superhydrophobic films is manufacture of anti-rain surfaces which was discussed by Liu et al. (Cui et al., 2017). They acquired contact angles above 170° through calcination of polydimethylsiloxane on glass and modification with CVD. It was observed that contact angle reduced over a constant period of time in acidic and alkaline solutions. The reduction, of course, was less intensely in acidic solutions due to changes in morphology of roughness structure on surface. The same morphology was entirely destructed in alkaline solutions. Then, it may be concluded that these films had a desirable performance in both acidic and neutral media.

Cai et al. (Cai et al., 2015) managed to form wooden superhydrophobic films through immersion in solution. They used lauryl aldehyde and lauric acid for surface modification and investigated adhesiveness and stability of films. It was observed that the sample saturated with lauric acid lost superhydrophobic properties in all pH ranges except from 6 to 7 due to loss of the adsorbed acid. In result, the air layer left the film and droplets could penetrate into the coating. However, regarding the sample saturated with lauryl aldehyde, higher stability rates were observed within all pH ranges.

Formation of antibacterial superhydrophobic films containing Ag by means of sol-gel method was investigated by Heinonen et al. (Heinonen et al., 2014). It was observed that after immersion for 8 weeks, the highest concentrations of Ag ions were found in extremely acidic and alkaline solutions. In order to investigate the effect of silver, immersion test was carried out on silver-free films under harsh conditions. As seen in SEM micrographs in Fig. 34, The film was entirely dissolved in acidic solutions and wetting angle plummeted to 100° at alkaline pH ranges. Besides, contact angle did not vary notably in neutral and mild alkaline media.

SEM micrographs of the sample without silver after immersion for 8 weeks in (a) harsh acidic and (b) harsh alkaline media (Heinonen et al., 2014)

Also in Fig. 35, SEM micrographs of silver-containing superhydrophobic samples shows that sample exposed to highly acidic solution has been completely desolved. However, the one immersed in sever alkaline media has shown a flaky structure in comparison with the silver-free sample which has no specific structure after exposure.

SEM micrographs of the sample with silver after immersion for 8 weeks in (a) harsh acidic and (b) harsh alkaline media (Heinonen et al., 2014).

There have been many studies conducted on formation of superhydrophobic films by this technique which are summarized in Table 7.

Table 7 Results of studies conducted based on contact angle versus pH variations.

Substrate	Method	SH agent	CA°	Immersion conditions	Chemical stability	Reference
Polyester sponge	Sol-gel	PMHS-TEOS	>150	1 < pH < 14	Good	Guo et al. (2015b)
Glass	Phase separation	BMA-BDO-EDMA-NMP	159.5	Acid, alkali, salt aqueous solution	Good	Liu et al. (2014a)
Copper	Electrolytic	Ethanolic stearic acid	156–162	1 < pH < 14	Good	Tan et al. (2015)
Wood	Immersion	TEOS	>150	1 < pH < 14	Good	Li et al. (2016)
AZ91D	ED	Stearic acid	167	1 < pH < 14	Good	She et al. (2013b)
Copper	Immersion	Stearic acid	163	2 < pH < 12	Good	Liu et al. (2014a)
Al alloy	Anodization	Myristic acid	155.6	DI water, ethanol	Good	Zheng et al. (2015)
Al alloy	Anodization	Myristic acid	155.2	1 < pH < 12	Good	Zheng et al. (2016)
Zn	Galvanic replacement reaction	Ethanol-PFDT	>150	1 < pH < 13	Good	Xu et al. (2012)
Al alloy	Laser marking	Ethanol-PFDTCS	155.1	1 < pH < 14	Good	Tang et al. (2016)
AZ91D magnesium alloy	Electrodeposition and chemical modification	Stearic acid	158.5	1 < pH < 13	Good	She et al. (2017b)
High-purity aluminum foils	Versatile one step electrodeposition	Stearic acid	>155	1 < pH < 14	Good	Guo et al. (2015a)
Copper mesh	Electrodeposition	Lauric acid	155.5	1 < pH < 14	Good	She et al. (2017a)
Carbon steel	One-step electrodeposition	Lanthanum nitrate	160	1 < pH < 13	Good	Yang et al. (2015)
Iron	Phosphate, Cu co-deposition in phosphating bath	FAS-17	160	1 < pH < 14	Good	Zhang et al. (2017b)
Various	One-step sol–gel electrochemistry route method	DTMS HTMS	>150	4 < pH < 14	Good	Wu et al. (2014c,d)
Copper mesh	Solution-immersion	Triazinedithiolsilane	>150	3 < pH < 13	Good	Wang et al. (2017b)
Wood	Solution-immersion	Stearic acid	155	1 < pH < 14	Good	Gao et al. (2015b)
Cotton	Covalent deposition method	Trimethoxysilane	158	1 < pH < 14	Good	Zhang et al. (2016e)
NMOF-1	Solution-immersion	OPE-C18	>155	1 < pH < 14	Good	Roy et al. (2016)
Aluminum	Anodization	FAS	156	0 < pH < 14	Good	Wang et al. (2017a)
AZ31	Solution-immersion	Fluoroalkylsilane	>142	1 < pH < 14	Good	Ishizaki and Saito (2010)
Copper	Oxidation − reduction reaction	–	>160	1 < pH < 14	Good	Lee et al. (2012)
Mg-Mn-Ce magnesium plate	Electrodeposition	Myristic acid	159.8	1 < pH < 14	Good	Liu et al. (2014a)
Various	Anti-deposition route method	Stearic acid	>150	1 < pH < 13	Good	Si et al. (2016)
Copper	Electrodeposition and heat-treatment	AC-FAS	162	1 < pH < 13	Good	Koishi et al. (2009)

6.3.2

6.3.2 Contact angle versus immersion time

Another highly employed technique for investigation of chemical stability is evaluation of contact angle of a droplet on surface as a function of immersion time in any sort of solution. This approach may be used in a single solution to evaluate stability or in different media with various pH values in order to compare the stability in different media. The obtained data are eventually plotted on a curve whose abscissa is immersion time and ordinate is contact angle or droplet sliding angle on the surface. This technique has been used in many cases regarding formation of superhydrophobic films. Wu et al. (Wu et al. (2014c,d)) developed surfaces to separate water from organic materials such as oil through applying superhydrophobic films on polyester substrates by means of dip coating and saturation with TOES and n-HDTOES. Through immersion in different solutions after long periods, it was observed that immersion time did not significantly affect superhydrophobic properties. It seemed that the reason of desirable performance was strong HD-silica/HD-polymer bonds with the substrate as well as stability of the nanocomposite in organic media such as crude oil.

Seeking to develop and apply superhydrophobic properties in textile industries, Li et al. (Fang et al., 2017) produced superhydrophobic cotton fabrics using copolymer materials which maintained a high contact angle (above 147°) after immersion in different pH solutions for 96 h. This can be realized as fairly high stability in acidic, neutral and alkaline solutions. The high lifetime is equivalent bonds between fluorine-containing polymeric chains and the cotton fabrics. Yang et al. (Yang et al., 2017) also improved stability in superhydrophobic epoxy films. They managed to keep contact angle above 150° in neutral, harshly acidic and harshly alkaline solutions for long exposure by random distribution of fluoro-graphene nano-planes as could be seen in the micrographs presented in Fig. 36. This clearly indicated the favorable chemical stability of films under the aforementioned conditions. Superhydrophobic films with adhesiveness control capability were deposited on titanium substrates by Guo et al. (Guo et al. (2015a)) via thermal oxidation and self-adjustment technique. A rough, scaled oxide film was applied on surface by alternative heating and quenching cycles so that superhydrophobic properties were obtained. Fig. 37 illustrates dual-scale roughness of this structure.

FE-SEM micrographs of fluoro-graphene nano-planes randomly distributed on the surface (Yang et al., 2017).

FE-SEM micrographs of thermally oxidized samples at 1100 °C for 15-min periods (M. Guo et al. (2015a)).

After immersion in harshly corrosive media, contact angle reduced over time which was due to a gradual decrease in surface superhydrophobic groups (N-ODTCS and n-hexane) as they have high affinity in reactions with extreme acidic solutions. Hence, the film is much more destructible in acidic environments. Within the first 5 days of immersion, contact angle remained above 150° in both types of solutions; however, this parameter plummeted to 146° in acidic media in long term while it yet remained above 150° in alkaline solutions.

The above technique may also be used in study of self-cleaning surfaces. For instance, Zheng et al. (Zheng et al. (2016, 2015)) investigated the stability of their films by pH variations. Superhydrophobic properties were not considerably affected after immersion in deionized water for 19 days.

As mentioned previously, this technique is well-known broadly used approach in investigation of chemical stability. The results obtained in several works conducted based on pH versus contact angle variations technique are presented in Table 8.

Table 8 Some of the works conducted based on pH versus contact variations technique.

Substrate	Method	SH agent	CA°	Immersion conditions	Chemical stability	Reference
Hierarchical aluminum	Acid etching and subsequent boiling water treatment	ABS-PC-PMMA-PS-PU	>150	pH = 1, 14	Good	Long et al. (2016)
Aluminum	In-situ growth process	Stearic acid	152.1	21–36 days in an specific solution	Good	Liang et al. (2013)
Steel	Etching and solution-immersion	Stearic acid	158	24 h in 3.5% NaCl sol.	Good	Zhang et al. (2017b)
Stainless steel mesh	One-step vapor deposition	PDMS	>160	40mins in NaOH and HCl	Good	Kim et al. (2016)
Cotton	MWCNTs coating	Nafion	154.6	96 h in water	Good	Zou et al., xxxx
Aluminum	Etching with ferric chloride	FDTS-PDMS-MTS	>150	72 h for alkali an acidic sol-48 h for ionic sol	Good	Maitra et al. (2014)
Cotton	Single-pot coating solution	Fluorinated alkyl silane	163	96 h in various organic solvents and aqueous solutions	Good	Zeng et al. (2015)
Copper	Electrodeposition	1-Dodecanethiol /polydopamine	154	In 3.5 wt% NaCl solution for 35 days	Good	Liu et al. (2014a)
Various	Surface-functionalized quartz sand nanoparticles	Polyvinylchloride	>150	In water for 30 days	Good till the 20th day	Qu et al. (2016)
–	Gel immersion	Fluorosilane	>150	In pH = 1,14 for 30 mins	Good	Zhang et al. (2017a)
Alumina	Onestep anodization process	PDES - stearic acid	>150	In diverse organic solvents	Good	Peng et al. (2005)

6.3.3

6.3.3 Acid rain test

Sometimes, working conditions decree that in addition to mechanical stability, chemical stability against acid rain most be studied. Here, sample is subjected to simulated acid rain with different pH values. The pH of simulation solution is generally adjusted with various concentrations of sulfuric acid. Due to complexity of simulation process, this technique is rarely used by researchers in study of chemical stability of coatings. For example, Zheng et al. (Zheng et al., 2016) conducted acid rain test within a pH range of 1 to 4 and at a controlled pH value of 5.6. The sample was exposed to simulated rain for 12 h. Similar to the results of other experiments, the film maintained superhydrophobic after 12 h of exposure to acid rain.

6.3.4

6.3.4 Droplet test in vapor-saturated atmosphere

Instead of direct droplet test, sample is enclosed by an isolated cell saturated with vapor of the intended vapor. The required data including contact angle and droplet sliding threshold angle are extracted after formation of droplets on surface. This technique is also less frequently used for chemical stability investigation due to complexity of the required data.

Emelyanenko et al. (Emelyanenko et al., 2015) formed nano-texture superhydrophobic surfaces on stainless steel substrates. They used laser and chemical adsorption of fluoro exi-silane to achieve a contact angle above 170° after immersion for 24 h. Xiao et al. (Xiao et al., 2016) reported that films produced on oxidized aluminum substrates had a contact angle above 150° after exposure for 60 h in an atmosphere saturated with NaCl vapor. This indicates high stability of coatings in saline corrosive media. However, droplet sliding angle increased by 90° which cannot be acceptable. They explained that this phenomenon is caused by facilitation of a continuous contact line among solid, liquid and vapor phases through integration of distilled water droplets. The droplets are mixed with NaCl solution so that the locked air bags are isolated and consequently more power is required to encounter the negative pressure. Multiple degrees of drop in contact angle was reported by She et al. (She et al. (2013b)) in Ni-Co films deposited on magnesium after exposure to harsh acidic and alkaline vapors for 36 h. Superhydrophobic properties were observed to remain after the experiment.

6.4

6.4 Chemical stability improvement approaches

As it was observed previously, depending on the chemical composition, the deposited film may have various scales of lifetime and stability in different media. According to the stated mechanisms for removal of chemical stability including application of more stable functional groups to reduce surface energy or use of self-repairing mechanism in coatings, there may be various approaches for improvement of lifetime of coatings.

7 Mechanical stability

7.1

7.1 Necessity of mechanical stability

Under various applications, superhydrophobic films are typically applied on to different surfaces so that wear processes may be induced between layers. Being so fragile, superhydrophobic films will lose their superhydrophobic properties as soon as they contact with an external surface. Thus, high mechanical stability is a major requirement for industrial applications of superhydrophobic films. In this section, several issues such as fading of superhydrophobic properties due to mechanical loadings, mechanical stability evaluation tests and recent developments in improving mechanical stability are discussed.

7.2

7.2 Fading mechanism of superhydrophobicity due to mechanical contacts

As mentioned earlier, it is necessary to create the cassie-baxter state in which water cannot penetrate through rough surfaces in order to achieve superhydrophobic properties with a high contact angle and a low residual angle. In Wenzel’s wetting state, water penetrates into a rough surface which results in higher slide angles. In general, it may be stated that cassie-baxter roughness state fades; water may penetrate into the rough surfaces and extinguish superhydrophobic properties. Mechanical fragility of superhydrophobic textures in surface causes creation of the Wenzel’s state as soon as a contact is made between internal and external surfaces. Therefore, the droplet and surface are locked with each other and their adhesiveness improves leading to fading of superhydrophobic properties (see in Fig. 38). Then, it may be realized that superhydrophobic properties reduce through two mechanisms: first, decrease of surface roughness and transition to the Wenzel’s state increases the contact area between water and surface and second, surface may lose its inherent hydrophobicity due to contamination with hydrophilic species.

Schematic of fading mechanism of superhydrophobicity due to mechanical contact.

7.3

7.3 Important approaches for improvement of mechanical stability

So far, great deals of studies have been conducted on improvement of mechanical stability in superhydrophobic films. This section is allocated to a review on the newest approaches for improving the mechanical stability in superhydrophobic films. As it was mentioned earlier, in order to achieve superhydrophobic properties, it is required to procure the cassie-baxter state. Note that transition from cassie-baxter to the Wenzel’s state fades superhydrophobic properties of the surface. An interesting method to increase mechanical stability in superhydrophobic surfaces even after application of mechanical loads is creation of dual scale surface roughness (Chen et al., 2016). In this case, a stable cassie-baxter state is reached which does not fade even after application of external loads. Xiu et al. (Xiu et al., 2010), investigated the effect of dual scale surface roughness on mechanical stability of silicon superhydrophobic films by means of wear tests and compared the results with surface roughness and they observed that noticeable variations occurred in increase of residual contact angle where the water droplet causes mechanical destruction on the surface and penetrates into the rough surface increasing the contact angle. It was reported that silicon superhydrophobic films with dual scale surface roughness showed an excellent mechanical stability. SEM studies revealed that only cone peaks undergo destruction in surfaces with dual scale roughness and the rough parts in the valley remains intact. Hence, the contact angle still has a large value. Using the same concept, there were other researchers that attempted to improve mechanical stability of superhydrophobic films (Zimmermann et al., 2008).

Since increase in inherent strength of a superhydrophobic surface texture leads to maintenance of Cassie-Baxter state, an important approach to enhance mechanical stability in a superhydrophobic film appears to be increasing the inherent strength in that superhydrophobic film. A practical technique for this purpose is fabrication of nanocomposite films (Ebert and Bhushan, 2012; Tadanaga et al., 2003; Zhu et al., 2011 ) implementing hydrophobic nanoparticles where grain size reduces and a new area is exposed as surface wearing process continues. Another approach which is used to improve inherent strength and consequently mechanical stability in superhydrophobic films is alloying of the surface texture through electrodeposition processes.

Mechanical stability in superhydrophobic films can also be improved by means of a hydrophobic bulk substance. Usually, a typical rough film may be produced via any available technique; then, its surface is modified with chemical treatment by applying a material with low surface energy (e.g. fatty acids) on the surface so that the superhydrophobic film is obtained. In this case, after the superhydrophobic film is worn, superhydrophobic properties are naturally lost. Thus, if the superhydrophobic film is produced totally with a hydrophobic material, new superhydrophobic surface is constantly exposed throughout the wearing process and mechanical stability improves. The last method to improve mechanical stability in superhydrophobic films discussed here is using self-repairing films. Such surfaces are capable of repairing the worn surfaces and maintain superhydrophobic properties (Ionov and Synytska, 2012; Li et al., 2010). In this field many studies have been done. For example, a micro-arc oxidation (MAO)/zinc stearate (ZnSA) composite coating was fabricated on Mg-4Li-1Ca alloy by means of MAO and subsequent sealing with electrodeposition of a superhydrophobic ZnSA. Corrosion resistance improvement of fabricated coating was attributed to self-healing property (Cui et al., 2017). Also Superhydrophobic Mg(OH)₂/Mg-Al Layered Double Hydroxide coating was fabricated on Mg alloys and high resistance improvement of superhydrophobic coating was ascribed to self-healing property (Zhang et al., 2016d).

8 Concluding remarks and future trends

In this work, a brief overview was conducted on methods of creating superhydrophobic surfaces and also the application of superhydrophobic surfaces was investigated. The main focus of this article was on the corrosion behavior as well as chemical and mechanical stability of developed superhydrophobic coatings. According to this study, it can be concluded that superhydrophobic surfaces created by different micro and nano surface roughness methods enhance the corrosion resistance of the substrate, as the air is trapped in them and prevents the transmission of electron and ion between the substrate and electrolyte. Moreover, the created Laplace pressure prevents the entrance of electrolyte to the substrate, which also improves the corrosion resistance of the surface. In addition, based on the overall results of this study, it can be found that the wetting angle is directly related to the corrosion resistance of surface; by increasing the wetting angle, correlation of the substrate and the corrosive species is decreased; which consequently increases the corrosion resistance. One of the main drawbacks of using superhydrophobic surfaces is their low mechanical and chemical stability when being exposed to corrosive environments. Based on this, recent advanced in chemical and mechanical stability enhancement were discussed in this paper.

As noted earlier, most scholars believe that the Laplace pressure and trapped air can improve the corrosion resistance of these surfaces. But, it seems that more extensive studies are required to understand the mechanism of enhanced corrosion resistance of superhydrophobic surfaces. Further studies are needed to increase the mechanical and chemical stability of these surfaces. According to the most of the reviewed articles, there is no comprehensive standard for assessing the mechanical stability of these surfaces and more studies must be conducted to standardize these cases. By reading this article and other reviews it can be found that most studies conducted in the case of corrosion resistance included corrosion resistance studies of superhydrophobic surfaces fabricated by deposition via electrical and chemical methods. Therefore, studying the corrosion resistance of fabricated superhydrophobic surfaces by other methods is also required. In addition, most studies have been conducted in the laboratory and further examination for industrialization of these coatings is required.

References

Abramov A.A., Vasiliev A.N., Dubovaya O.V., Kovalev V.V., Vatsouro I.M., . Extraction of americium (III), plutonium (IV, V) and neptunium (V) with calixarenes. Mendeleev Commun.. 2012;22(5):260-262.
[Google Scholar]
Acatay K., Simsek E., Ow-Yang C., Menceloglu Y.Z., . Tunable, superhydrophobically stable polymeric surfaces by electrospinning. Angew. Chem. Int. Ed.. 2004;43(39):5210-5213.
[Google Scholar]
Akram Raza M., Kooij E.S., van Silfhout A., Poelsema B., . Superhydrophobic surfaces by anomalous fluoroalkylsilane self-assembly on silica nanosphere arrays. Langmuir. 2010;26(15):12962-12972.
[Google Scholar]
Aliofkhazraei M., Sabour Rouhaghdam A., Shahrabi T., . Abrasive wear behaviour of Si₃N₄/TiO₂ nanocomposite coatings fabricated by plasma electrolytic oxidation. Surf. Coat. Technol.. 2010;205(Supplement 1):S41-S46.
[CrossRef] [Google Scholar]
Andreeva N., Ishizaki T., Baroch P., Saito N., . High sensitive detection of volatile organic compounds using superhydrophobic quartz crystal microbalance. Sens. Actuators, B. 2012;164(1):15-21.
[Google Scholar]
Bagheri H., Aliofkhazraei M., Forooshani H.M., Rouhaghdam A.S., . Electrodeposition of the hierarchical dual structured (HDS) nanocrystalline Ni surface with high water repellency and self-cleaning properties. J. Taiwan Inst. Chem. Eng.. 2017;80:883-893.
[Google Scholar]
Bagheri H., Aliofkhazraei M., Forooshani H.M., Rouhaghdam A.S., . Facile fabrication of uniform hierarchical structured (UHS) nanocomposite surface with high water repellency and self-cleaning properties. Appl. Surf. Sci.. 2018;436:1134-1146.
[Google Scholar]
Bao B., Sun J., Gao M., Zhang X., Jiang L., Song Y., . Patterning liquids on inkjet-imprinted surfaces with highly adhesive superhydrophobicity. Nanoscale. 2016;8(18):9556-9562.
[Google Scholar]
Barkhudarov P.M., Shah P.B., Watkins E.B., Doshi D.A., Brinker C.J., Majewski J., . Corrosion inhibition using superhydrophobic films. Corros. Sci.. 2008;50(3):897-902.
[Google Scholar]
Barshilia H.C., Chaudhary A., Kumar P., Manikandanath N.T., . Wettability of Y₂O₃: a relative analysis of thermally oxidized, reactively sputtered and template assisted nanostructured coatings. Nanomaterials. 2012;2(1):65-78.
[Google Scholar]
Blossey R., . Self-cleaning surfaces—virtual realities. Nature Mater.. 2003;2(5):301-306.
[Google Scholar]
Boinovich L., Emelyanenko A., . A wetting experiment as a tool to study the physicochemical processes accompanying the contact of hydrophobic and superhydrophobic materials with aqueous media. Adv. Colloid Interface Sci.. 2012;179:133-141.
[Google Scholar]
Bormashenko E., Bormashenko Y., . Non-stick droplet surgery with a superhydrophobic scalpel. Langmuir. 2011;27(7):3266-3270.
[Google Scholar]
Bravo J., Zhai L., Wu Z., Cohen R.E., Rubner M.F., . Transparent superhydrophobic films based on silica nanoparticles. Langmuir. 2007;23(13):7293-7298.
[Google Scholar]
Cai P., Bai N., Xu L., Tan C., Li Q., . Fabrication of superhydrophobic wood surface with enhanced environmental adaptability through a solution-immersion process. Surf. Coat. Technol.. 2015;277:262-269.
[Google Scholar]
Cao H., Zheng H., Liu K., Fu R., . Single-crystalline semiconductor In (OH) 3 nanocubes with bifunctions: superhydrophobicity and photocatalytic activity. Cryst. Growth Des.. 2009;10(2):597-601.
[Google Scholar]
Carotenuto G., Martorana B., Perlo P., Nicolais L., . A universal method for the synthesis of metal and metal sulfide clusters embedded in polymer matrices. J. Mater. Chem.. 2003;13(12):2927-2930.
[Google Scholar]
Cassie A., Baxter S., . Wettability of porous surfaces. Trans. Faraday Soc.. 1944;40:546-551.
[Google Scholar]
Chakrabarty S., Nisenholt M., Wynne K.J., . PDMS–fluorous polyoxetane–PDMS triblock hybrid elastomers: tough and transparent with novel bulk morphologies. Macromolecules. 2012;45(19):7900-7913.
[Google Scholar]
Chen W., McCarthy T.J., . Layer-by-layer deposition: a tool for polymer surface modification. Macromolecules. 1997;30(1):78-86.
[Google Scholar]
Chen X., Gong Y., Li D., Li H., . Robust and easy-repairable superhydrophobic surfaces with multiple length-scale topography constructed by thermal spray route. Colloids Surf., A. 2016;492:19-25.
[Google Scholar]
Chen X., Yuan J., Huang J., Ren K., Liu Y., Lu S., Li H., . Large-scale fabrication of superhydrophobic polyurethane/nano-Al 2 O 3 coatings by suspension flame spraying for anti-corrosion applications. Appl. Surf. Sci.. 2014;311:864-869.
[Google Scholar]
Chen Z., Hao L., Chen A., Song Q., Chen C., . A rapid one-step process for fabrication of superhydrophobic surface by electrodeposition method. Electrochim. Acta. 2012;59:168-171.
[Google Scholar]
Cheng Y., Lu S., Xu W., . Controllable wettability of micro-and nano-dendritic structures formed on aluminum substrates. New J. Chem.. 2015;39(8):6602-6610.
[Google Scholar]
Cheng Y., Lu S., Xu W., Wen H., . Fabrication of Au–AlAu 4–Al₂O₃ superhydrophobic surface and its corrosion resistance. RSC Adv.. 2015;5(20):15387-15394.
[Google Scholar]
Cho D.J., Kim S.E., Seo E., Lee M.C., Lee J.M., Ko J.S., . Underwater micro gas detector. Sens. Actuators, B. 2013;188:347-353.
[Google Scholar]
Choi J.H., Kim Y.M., Park Y.W., Park T.H., Dong K.Y., Ju B.K., . Hydrophilic dots on hydrophobic nanopatterned surfaces as a flexible gas barrier. Langmuir. 2009;25(12):7156-7160.
[Google Scholar]
Chu Z., Seeger S., . Superamphiphobic surfaces. Chem. Soc. Rev.. 2014;43(8):2784-2798.
[CrossRef] [Google Scholar]
Cote C., Rosas O., Basseguy R., . Geobacter sulfurreducens: An iron reducing bacterium that can protect carbon steel against corrosion? Corros. Sci.. 2015;94:104-113.
[Google Scholar]
Coulson S., Woodward I., Badyal J., Brewer S., Willis C., . Super-repellent composite fluoropolymer surfaces. J. Phys. Chem. B. 2000;104(37):8836-8840.
[Google Scholar]
Crick C.R., Bear J.C., Southern P., Parkin I.P., . A general method for the incorporation of nanoparticles into superhydrophobic films by aerosol assisted chemical vapour deposition. J. Mater. Chem. A. 2013;1(13):4336-4344.
[Google Scholar]
Cui L.-Y., Liu H.-P., Zhang W.-L., Han Z.-Z., Deng M.-X., Zeng R.-C., Wang Z.-L., . Corrosion resistance of a superhydrophobic micro-arc oxidation coating on Mg-4Li-1Ca alloy. J. Mater. Sci. Technol. 2017
[Google Scholar]
Cui X.-J., Lin X.-Z., Liu C.-H., Yang R.-S., Zheng X.-W., Gong M., . Fabrication and corrosion resistance of a hydrophobic micro-arc oxidation coating on AZ31 Mg alloy. Corros. Sci.. 2015;90:402-412.
[Google Scholar]
Cui Z., Zhang F., Wang L., Xu S., Guo X., . In situ crystallized zirconium phenylphosphonate films with crystals vertically to the substrate and their hydrophobic, dielectric, and anticorrosion properties. Langmuir. 2009;26(1):179-182.
[Google Scholar]
Darband G.B., Aliofkhazraei M., Hamghalam P., Valizade N., . Plasma electrolytic oxidation of magnesium and its alloys: mechanism, properties and applications. J. Magnes. Alloys 2017
[Google Scholar]
Darmanin T., De Givenchy E.T., Amigoni S., Guittard F., . Superhydrophobic surfaces by electrochemical processes. Adv. Mater.. 2013;25(10):1378-1394.
[Google Scholar]
Darmanin T., Guittard F., . Recent advances in the potential applications of bioinspired superhydrophobic materials. J. Mater. Chem. A. 2014;2(39):16319-16359.
[Google Scholar]
Darmanin T., Tarrade J., Celia E., Bellanger H., Guittard F., . Superoleophobic meshes with relatively low hysteresis and sliding angles by electropolymerization: importance of polymer-growth control. ChemPlusChem. 2014;79(3):382-386.
[Google Scholar]
Darmanin T., Tarrade J., Celia E., Guittard F.d.r., . Superoleophobic meshes with high adhesion by electrodeposition of conducting polymer containing short perfluorobutyl chains. J. Phys. Chem. C. 2014;118(4):2052-2057.
[Google Scholar]
Deng X., Mammen L., Zhao Y., Lellig P., Müllen K., Li C., Vollmer D., . Transparent, thermally stable and mechanically robust superhydrophobic surfaces made from porous silica capsules. Adv. Mater.. 2011;23(26):2962-2965.
[Google Scholar]
Dong H., Ye P., Zhong M., Pietrasik J., Drumright R., Matyjaszewski K., . Superhydrophilic surfaces via polymer− SiO₂ nanocomposites. Langmuir. 2010;26(19):15567-15573.
[Google Scholar]
Du X., He J., . A self-templated etching route to surface-rough silica nanoparticles for superhydrophobic coatings. ACS Appl. Mater. Interfaces. 2011;3(4):1269-1276.
[Google Scholar]
Durand N., Mariot D., Améduri B., Boutevin B., Ganachaud F., . Tailored covalent grafting of hexafluoropropylene oxide oligomers onto silica nanoparticles: toward thermally stable, hydrophobic, and oleophobic nanocomposites. Langmuir. 2011;27(7):4057-4067.
[Google Scholar]
Ebert D., Bhushan B., . Transparent, superhydrophobic, and wear-resistant coatings on glass and polymer substrates using SiO₂, ZnO, and ITO nanoparticles. Langmuir. 2012;28(31):11391-11399.
[Google Scholar]
Egorkin V., Vyaliy I., Minaev A., Sinebryukhov S., Gnedenkov S., . Morphological features and electrochemical properties of the hydrophobized sealed PEO-coatings on Al alloy. Solid State Phenom.. 2016;245
[Google Scholar]
Egorkin, V., Vyaliy, I., Sinebryukhov, S., Gnedenkov, S., 2015. Evaluation of electrochemical properties of the PEO-coatings treated with hydrophobic agent solution on aluminium alloy. In: Paper Presented at the Solid State Phenomena.
Emelyanenko A.M., Shagieva F.M., Domantovsky A.G., Boinovich L.B., . Nanosecond laser micro- and nanotexturing for the design of a superhydrophobic coating robust against long-term contact with water, cavitation, and abrasion. Appl. Surf. Sci.. 2015;332:513-517.
[Google Scholar]
Erbil H.Y., Cansoy C.E., . Range of applicability of the Wenzel and Cassie−Baxter equations for superhydrophobic surfaces. Langmuir. 2009;25(24):14135-14145.
[Google Scholar]
Esmailzadeh S., Khorsand S., Raeissi K., Ashrafizadeh F., . Microstructural evolution and corrosion resistance of super-hydrophobic electrodeposited nickel films. Surf. Coat. Technol.. 2015;283:337-346.
[Google Scholar]
Fadeev A.Y., Helmy R., Marcinko S., . Self-assembled monolayers of organosilicon hydrides supported on titanium, zirconium, and hafnium dioxides. Langmuir. 2002;18(20):7521-7529.
[Google Scholar]
Fan M.M., Liu H.F., Dong Z.H., . Microbiologically influenced corrosion of X60 carbon steel in CO₂-saturated oilfield flooding water. Mater. Corros.. 2013;64(3):242-246.
[Google Scholar]
Fan X., Liu Y., Quan X., Zhao H., Chen S., Yi G., Du L., . High desalination permeability, wetting and fouling resistance on superhydrophobic carbon nanotube hollow fiber membrane under self-powered electrochemical assistance. J. Membr. Sci.. 2016;514:501-509.
[Google Scholar]
Fan Y., Chen S., Zhao H., Liu Y., . Distillation membrane constructed by TiO₂ nanofiber followed by fluorination for excellent water desalination performance. Desalination. 2017;405:51-58.
[Google Scholar]
Fan Y., He Y., Luo P., Chen X., Liu B., . A facile electrodeposition process to fabricate corrosion-resistant superhydrophobic surface on carbon steel. Appl. Surf. Sci.. 2016;368:435-442.
[Google Scholar]
Fan Y., Li C., Chen Z., Chen H., . Study on fabrication of the superhydrophobic sol–gel films based on copper wafer and its anti-corrosive properties. Appl. Surf. Sci.. 2012;258(17):6531-6536.
[Google Scholar]
Fang L.J., Li Y.H., Liu P.F., Wang D.P., Zeng H.D., Wang X.L., Yang H.G., . Facile fabrication of large-aspect-ratio g-C₃N₄ nanosheets for enhanced photocatalytic hydrogen evolution. ACS Sustain. Chem. Eng.. 2017;5(3):2039-2043.
[CrossRef] [Google Scholar]
Farhadi S., Aliofkhazraei M., Darband G.B., Abolhasani A., Rouhaghdam A.S., . Corrosion and wettability of PEO coatings on magnesium by addition of potassium stearate. J. Magnes. Alloys. 2017;5(2):210-216.
[Google Scholar]
Farhadi S., Aliofkhazraei M., Darband G.B., Abolhasani A., Rouhaghdam A.S., . Wettability and corrosion behavior of chemically modified plasma electrolytic oxidation nanocomposite coating. J. Mater. Eng. Perform.. 2017;26(10):4797-4806.
[Google Scholar]
Farhadi S.S., . Effect of Fatty Acids Additive in Electrolyte on Wettability of PEO Nanocomposite Coating on Mg, Ti and Al. Tarbiat Modares University; 2014. (MSc)
Feng L., Che Y., Liu Y., Qiang X., Wang Y., . Fabrication of superhydrophobic aluminium alloy surface with excellent corrosion resistance by a facile and environment-friendly method. Appl. Surf. Sci.. 2013;283:367-374.
[Google Scholar]
Feng L., Li S., Li H., Zhai J., Song Y., Jiang L., Zhu D., . Super-hydrophobic surface of aligned polyacrylonitrile nanofibers. Angew. Chem.. 2002;114(7):1269-1271.
[Google Scholar]
Feng L., Yan Z., Qiang X., Liu Y., Wang Y., . Facile formation of superhydrophobic aluminum alloy surface and corrosion-resistant behavior. Appl. Phys. A. 2016;122(3):1-14.
[Google Scholar]
Feng L., Zhang H., Wang Z., Liu Y., . Superhydrophobic aluminum alloy surface: fabrication, structure, and corrosion resistance. Colloids Surf., A. 2014;441:319-325.
[Google Scholar]
Feng L., Zhang Z., Mai Z., Ma Y., Liu B., Jiang L., Zhu D., . A super-hydrophobic and super-oleophilic coating mesh film for the separation of oil and water. Angew. Chem. Int. Ed.. 2004;43(15):2012-2014.
[Google Scholar]
Feng L., Zhu Y., Fan W., Wang Y., Qiang X., Liu Y., . Fabrication and corrosion resistance of superhydrophobic magnesium alloy. Appl. Phys. A. 2015;120(2):561-570.
[Google Scholar]
Forooshani H.M., Aliofkhazraei M., Rouhaghdam A.S., . Superhydrophobic aluminum surfaces by mechanical/chemical combined method and its corrosion behavior. J. Taiwan Inst. Chem. Eng.. 2017;72:220-235.
[Google Scholar]
Gao H., Lu S., Xu W., Szunerits S., Boukherroub R., . Controllable fabrication of stable superhydrophobic surfaces on iron substrates. RSC Adv.. 2015;5(51):40657-40667.
[Google Scholar]
Gao R., Liu Q., Wang J., Zhang X., Yang W., Liu J., Liu L., . Fabrication of fibrous szaibelyite with hierarchical structure superhydrophobic coating on AZ31 magnesium alloy for corrosion protection. Chem. Eng. J.. 2014;241:352-359.
[Google Scholar]
Gao Z., Ma M., Zhai X., Zhang M., Zang D., Wang C., . Improvement of chemical stability and durability of superhydrophobic wood surface via a film of TiO2 coated CaCO3 micro-/nano-composite particles. RSC Adv.. 2015;5(79):63978-63984.
[Google Scholar]
Garrod R., Harris L., Schofield W., McGettrick J., Ward L., Teare D., Badyal J., . Mimicking a stenocara beetle's back for microcondensation using plasmachemical patterned superhydrophobic-superhydrophilic surfaces. Langmuir. 2007;23(2):689-693.
[Google Scholar]
Ge D., Yang L., Wu G., Yang S., . Spray coating of superhydrophobic and angle-independent coloured films. Chem. Commun.. 2014;50(19):2469-2472.
[Google Scholar]
Genzer J., Efimenko K., . Recent developments in superhydrophobic surfaces and their relevance to marine fouling: a review. Biofouling. 2006;22(5):339-360.
[Google Scholar]
Gnedenkov S., Sinebryukhov S., Egorkin V., Mashtalyar D., Alpysbaeva D., Boinovich L., . Wetting and electrochemical properties of hydrophobic and superhydrophobic coatings on titanium. Colloids Surf., A. 2011;383(1):61-66.
[Google Scholar]
Gnedenkov S., Sinebryukhov S., Egorkin V., Mashtalyar D., Emelyanenko A., Boinovich L., . Electrochemical properties of the superhydrophobic coatings on metals and alloys. J. Taiwan Inst. Chem. Eng.. 2014;45(6):3075-3080.
[Google Scholar]
Good R.J., . A thermodynamic derivation of Wenzel's modification of Young's equation for contact angles; together with a theory of hysteresis. J. Am. Chem. Soc.. 1952;74(20):5041-5042.
[Google Scholar]
Goodwyn P.P., Maezono Y., Hosoda N., Fujisaki K., . Waterproof and translucent wings at the same time: problems and solutions in butterflies. Naturwissenschaften. 2009;96(7):781-787.
[Google Scholar]
Grignard B., Vaillant A., de Coninck J., Piens M., Jonas A.M., Detrembleur C., Jerome C., . Electrospinning of a functional perfluorinated block copolymer as a powerful route for imparting superhydrophobicity and corrosion resistance to aluminum substrates. Langmuir. 2010;27(1):335-342.
[Google Scholar]
Gu S.Y., Wang Z.M., Li J.B., Ren J., . Switchable Wettability of Thermo-Responsive Biocompatible Nanofibrous Films Created by Electrospinning. Macromol. Mater. Eng.. 2010;295(1):32-36.
[Google Scholar]
Gui X., Li H., Wang K., Wei J., Jia Y., Li Z., Wu D., . Recyclable carbon nanotube sponges for oil absorption. Acta Mater.. 2011;59(12):4798-4804.
[Google Scholar]
Guo F., Su X., Hou G., Liu Z., Mei Z., . Fabrication of superhydrophobic TiO₂ surface with cactus-like structure by a facile hydrothermal approach. Colloids Surf., A. 2012;395:70-74.
[Google Scholar]
Guo J., Wang L., Wang S., Liang J., Xue Q., Yan F., . Preparation and performance of a novel multifunctional plasma electrolytic oxidation composite coating formed on magnesium alloy. J. Mater. Sci.. 2009;44(8):1998-2006.
[Google Scholar]
Guo M., Kang Z., Li W., Zhang J., . A facile approach to fabricate a stable superhydrophobic film with switchable water adhesion on titanium surface. Surf. Coat. Technol.. 2015;239:227-232.
[Google Scholar]
Guo P., Zhai S., Xiao Z., An Q., . One-step fabrication of highly stable, superhydrophobic composites from controllable and low-cost PMHS/TEOS sols for efficient oil cleanup. J. Colloid Interface Sci.. 2015;446:155-162.
[Google Scholar]
Han J.T., Zheng Y., Cho J.H., Xu X., Cho K., . Stable superhydrophobic organic-inorganic hybrid films by electrostatic self-assembly. J. Phys. Chem. B. 2005;109(44):20773-20778.
[Google Scholar]
Hao J.Y., Wang Y.Y., Tong X.L., Jin G.Q., Guo X.Y., . Photocatalytic hydrogen production over modified SiC nanowires under visible light irradiation. Int. J. Hydrogen Energy. 2012;37(20):15038-15044.
[CrossRef] [Google Scholar]
Hashemzadeh M., Raeissi K., Ashrafizadeh F., Khorsand S., . Effect of ammonium chloride on microstructure, super-hydrophobicity and corrosion resistance of nickel coatings. Surf. Coat. Technol.. 2015;283:318-328.
[Google Scholar]
Hashim N.A., Liu Y., Li K., . Preparation of PVDF hollow fiber membranes using SiO₂ particles: the effect of acid and alkali treatment on the membrane performances. Ind. Eng. Chem. Res.. 2011;50(5):3035-3040.
[Google Scholar]
Hassan A., Wasim A., Jiang X., . Upscaling and its application in numerical simulation of long-term CO₂ storage. Greenh. Gases Sci. Technol.. 2012;2(6):408-418.
[Google Scholar]
He T., Wang Y., Zhang Y., Xu T., Liu T., . Super-hydrophobic surface treatment as corrosion protection for aluminum in seawater. Corros. Sci.. 2009;51(8):1757-1761.
[Google Scholar]
Heinonen S., Huttunen-Saarivirta E., Nikkanen J.P., Raulio M., Priha O., Laakso J., Levänen E., . Antibacterial properties and chemical stability of superhydrophobic silver-containing surface produced by sol-gel route. Colloids Surf. A: Physicochem. Eng. Aspects. 2014;453(1):149-161.
[Google Scholar]
Hench L.L., West J.K., . The sol-gel process. Chem. Rev.. 1990;90(1):33-72.
[Google Scholar]
Hermelin E., Petitjean J., Lacroix J.-C., Chane-Ching K.I., Tanguy J., Lacaze P.-C., . Ultrafast electrosynthesis of high hydrophobic polypyrrole coatings on a zinc electrode: applications to the protection against corrosion. Chem. Mater.. 2008;20(13):4447-4456.
[Google Scholar]
Hikita M., Tanaka K., Nakamura T., Kajiyama T., Takahara A., . Super-liquid-repellent surfaces prepared by colloidal silica nanoparticles covered with fluoroalkyl groups. Langmuir. 2005;21(16):7299-7302.
[Google Scholar]
Hintze P.E., Calle L.M., . Electrochemical properties and corrosion protection of organosilane self-assembled monolayers on aluminum 2024–T3. Electrochim. Acta. 2006;51(8):1761-1766.
[Google Scholar]
Hou W., Kang Z., . Preparation of duplex film through microarc oxidation coloring and polymer plating on Mg-Li alloy and its corrosion resistance. Int. J. Electrochem. Sci.. 2013;8:5613-5620.
[Google Scholar]
Howarter J.A., Youngblood J.P., . Self-cleaning and anti-fog surfaces via stimuli-responsive polymer brushes. Adv. Mater.. 2007;19(22):3838-3843.
[Google Scholar]
Howarter J.A., Youngblood J.P., . Self-cleaning and next generation anti-fog surfaces and coatings. Macromol. Rapid Commun.. 2008;29(6):455-466.
[Google Scholar]
Hu F., Xu P., Wang H., Byoung Kang U., Hu A., Li M., . Superhydrophobic and anti-corrosion Cu microcones/Ni–W alloy coating fabricated by electrochemical approaches. RSC Adv.. 2015;5(126):103863-103868.
[Google Scholar]
Huang Y., Sarkar D.K., Chen X., . Fabrication of corrosion resistance micro-nanostructured superhydrophobic anodized aluminum in a one-step electrodeposition process. Metals. 2016;6(3):47.
[Google Scholar]
Ionov L., Synytska A., . Self-healing superhydrophobic materials. Phys. Chem. Chem. Phys.. 2012;14(30):10497-10502.
[CrossRef] [Google Scholar]
Ishizaki T., Hieda J., Saito N., Saito N., Takai O., . Corrosion resistance and chemical stability of super-hydrophobic film deposited on magnesium alloy AZ31 by microwave plasma-enhanced chemical vapor deposition. Electrochim. Acta. 2010;55(23):7094-7101.
[Google Scholar]
Ishizaki T., Saito N., . Rapid formation of a superhydrophobic surface on a magnesium alloy coated with a cerium oxide film by a simple immersion process at room temperature and its chemical stability. Langmuir. 2010;26(12):9749-9755.
[Google Scholar]
Ishizaki T., Sakamoto M., . Facile formation of biomimetic color-tuned superhydrophobic magnesium alloy with corrosion resistance. Langmuir. 2011;27(6):2375-2381.
[Google Scholar]
Jiang J., Xu J., Liu Z., Deng L., Sun B., Liu S., Liu H., . Preparation, corrosion resistance and hemocompatibility of the superhydrophobic TiO₂ coatings on biomedical Ti-6Al-4V alloys. Appl. Surf. Sci.. 2015;347:591-595.
[Google Scholar]
Jiang Y., Wang Z., Yu X., Shi F., Xu H., Zhang X., Dehaen W., . Self-assembled monolayers of dendron thiols for electrodeposition of gold nanostructures: toward fabrication of superhydrophobic/superhydrophilic surfaces and pH-responsive surfaces. Langmuir. 2005;21(5):1986-1990.
[Google Scholar]
Jie H., Xu Q., Wei L., Min Y., . Etching and heating treatment combined approach for superhydrophobic surface on brass substrates and the consequent corrosion resistance. Corros. Sci.. 2016;102:251-258.
[Google Scholar]
Jitianu A., Doyle J., Amatucci G., Klein L.C., . Methyl modified siloxane melting gels for hydrophobic films. J. Sol-Gel Sci. Technol.. 2010;53(2):272-279.
[Google Scholar]
Jung S., Tiwari M.K., Doan N.V., Poulikakos D., . Mechanism of supercooled droplet freezing on surfaces. Nat. Commun.. 2012;3:615.
[Google Scholar]
Jung Y.C., Bhushan B., . Dynamic effects induced transition of droplets on biomimetic superhydrophobic surfaces. Langmuir. 2009;25(16):9208-9218.
[Google Scholar]
Kang Z., Lai X., Wang F., Long Y., Li Y., . Preparation of super-hydrophobic duplex-treated film on surface of Mg–Mn–Ce magnesium alloy and its corrosion resistance. Chin. J. Nonferr. Met.. 2011;21(2):283-289.
[Google Scholar]
Kavale M.S., Mahadik D., Parale V., Wagh P., Gupta S.C., Rao A.V., Barshilia H.C., . Optically transparent, superhydrophobic methyltrimethoxysilane based silica coatings without silylating reagent. Appl. Surf. Sci.. 2011;258(1):158-162.
[Google Scholar]
Khorsand S., Raeissi K., Ashrafizadeh F., . Corrosion resistance and long-term durability of super-hydrophobic nickel film prepared by electrodeposition process. Appl. Surf. Sci.. 2014;305:498-505.
[Google Scholar]
Khorsand S., Raeissi K., Ashrafizadeh F., Arenas M., Conde A., . Corrosion behaviour of super-hydrophobic electrodeposited nickel–cobalt alloy film. Appl. Surf. Sci.. 2016;364:349-357.
[Google Scholar]
Kim B.R., Kim D.H., Kim Y.D., . Superhydrophobic, flexible and gas-permeable membrane prepared by a simple one-step vapor deposition. Kor. J. Chem. Eng. 2016:1-6.
[Google Scholar]
Koishi T., Yasuoka K., Fujikawa S., Ebisuzaki T., Zeng X.C., . Coexistence and transition between Cassie and Wenzel state on pillared hydrophobic surface. Proc. Natl. Acad. Sci.. 2009;106(21):8435-8440.
[Google Scholar]
Kota A.K., Li Y., Mabry J.M., Tuteja A., . Hierarchically structured superoleophobic surfaces with ultralow contact angle hysteresis. Adv. Mater.. 2012;24(43):5838-5843.
[Google Scholar]
Kulinich S., Farhadi S., Nose K., Du X., . Superhydrophobic surfaces: are they really ice-repellent? Langmuir. 2010;27(1):25-29.
[Google Scholar]
Kulinich S., Farzaneh M., . How wetting hysteresis influences ice adhesion strength on superhydrophobic surfaces. Langmuir. 2009;25(16):8854-8856.
[Google Scholar]
Kulinich S., Farzaneh M., . Ice adhesion on super-hydrophobic surfaces. Appl. Surf. Sci.. 2009;255(18):8153-8157.
[Google Scholar]
Lakshmi R., Bharathidasan T., Basu B.J., . Superhydrophobic sol–gel nanocomposite coatings with enhanced hardness. Appl. Surf. Sci.. 2011;257(24):10421-10426.
[Google Scholar]
Latthe S.S., Sudhagar P., Devadoss A., Kumar A.M., Liu S., Terashima C., Fujishima A., . A mechanically bendable superhydrophobic steel surface with self-cleaning and corrosion-resistant properties. J. Mater. Chem. A. 2015;3(27):14263-14271.
[Google Scholar]
Lee S.-M., Kim K.-S., Pippel E., Kim S., Kim J.-H., Lee H.-J., . Facile route toward mechanically stable superhydrophobic copper using oxidation–reduction induced morphology changes. J. Phys. Chem. C. 2012;116(4):2781-2790.
[Google Scholar]
Li J., Wu R., Jing Z., Yan L., Zha F., Lei Z., . One-step spray-coating process for the fabrication of colorful superhydrophobic coatings with excellent corrosion resistance. Langmuir. 2015;31(39):10702-10707.
[Google Scholar]
Li K., Zeng X., Li H., Lai X., . A study on the fabrication of superhydrophobic iron surfaces by chemical etching and galvanic replacement methods and their anti-icing properties. Appl. Surf. Sci.. 2015;346:458-463.
[Google Scholar]
Li W., Xiong D., Gao X., Song W.G., Xia F., Liu L., . Self-supported Co-Ni-P ternary nanowire electrodes for highly efficient and stable electrocatalytic hydrogen evolution in acidic solution. Catal. Today 2016
[CrossRef] [Google Scholar]
Li Y., Li L., Sun J., . Bioinspired self-healing superhydrophobic coatings. Angew. Chem.. 2010;122(35):6265-6269.
[Google Scholar]
Li Y., Shi G., . Electrochemical growth of two-dimensional gold nanostructures on a thin polypyrrole film modified ITO electrode. J. Phys. Chem. B. 2005;109(50):23787-23793.
[Google Scholar]
Liang J., Hu Y., Fan Y., Chen H., . Formation of superhydrophobic cerium oxide surfaces on aluminum substrate and its corrosion resistance properties. Surf. Interf. Anal.. 2013;45(8):1211-1216.
[Google Scholar]
Liang J., Hu Y., Wu Y., Chen H., . Facile formation of superhydrophobic silica-based surface on aluminum substrate with tetraethylorthosilicate and vinyltriethoxysilane as co-precursor and its corrosion resistant performance in corrosive NaCl aqueous solution. Surf. Coat. Technol.. 2014;240:145-153.
[Google Scholar]
Lifton V.A., Simon S., Frahm R.E., . Reserve battery architecture based on superhydrophobic nanostructured surfaces. Bell Labs Tech. J.. 2005;10(3):81-85.
[Google Scholar]
Lin C.-Y., Lin K.-Y.A., Yang T.-W., Chen Y.-C., Yang H., . Self-assembled hemispherical nanowell arrays for superhydrophobic antireflection coatings. J. Colloid Interface Sci.. 2017;490:174-180.
[Google Scholar]
Lin Y., Shen Y., Liu A., Zhu Y., Liu S., Jiang H., . Bio-inspiredly fabricating the hierarchical 3D porous structure superhydrophobic surfaces for corrosion prevention. Mater. Des.. 2016;103:300-307.
[Google Scholar]
Liu B., Fu Y., Ruan W., He Y., Wang X., . Preparation of super-hydrophobic surfaces by using elastomer templates and UV-curable resins. Acta Poly. Sin.. 2008;2:155.
[Google Scholar]
Liu H., Szunerits S., Xu W., Boukherroub R., . Preparation of superhydrophobic coatings on zinc as effective corrosion barriers. ACS Appl. Mater. Interf.. 2009;1(6):1150-1153.
[Google Scholar]
Liu J., Xiao X., Shi Y., Wan C., . Fabrication of a superhydrophobic surface from porous polymer using phase separation. Appl. Surf. Sci.. 2014;297:33-39.
[Google Scholar]
Liu K., Jiang L., . Multifunctional integration: from biological to bio-inspired materials. ACS Nano. 2011;5(9):6786-6790.
[Google Scholar]
Liu L., Chen R., Liu W., Zhang Y., Shi X., Pan Q., . Fabrication of superhydrophobic copper sulfide film for corrosion protection of copper. Surf. Coat. Technol.. 2015;272:221-228.
[Google Scholar]
Liu M., Wang S., Wei Z., Song Y., Jiang L., . Bioinspired design of a superoleophobic and low adhesive water/solid interface. Adv. Mater.. 2009;21(6):665-669.
[Google Scholar]
Liu Q., Chen D., Kang Z., . One-step electrodeposition process to fabricate corrosion-resistant superhydrophobic surface on magnesium alloy. ACS Appl. Mater. Interf.. 2015;7(3):1859-1867.
[Google Scholar]
Liu Q., Kang Z., . One-step electrodeposition process to fabricate superhydrophobic surface with improved anticorrosion property on magnesium alloy. Mater. Lett.. 2014;137:210-213.
[CrossRef] [Google Scholar]
Liu T., Chen S., Cheng S., Tian J., Chang X., Yin Y., . Corrosion behavior of super-hydrophobic surface on copper in seawater. Electrochim. Acta. 2007;52(28):8003-8007.
[Google Scholar]
Liu T., Yin Y., Chen S., Chang X., Cheng S., . Super-hydrophobic surfaces improve corrosion resistance of copper in seawater. Electrochim. Acta. 2007;52(11):3709-3713.
[Google Scholar]
Liu W., Luo Y., Sun L., Wu R., Jiang H., Liu Y., . Fabrication of the superhydrophobic surface on aluminum alloy by anodizing and polymeric coating. Appl. Surf. Sci.. 2013;264:872-878.
[Google Scholar]
Liu W., Xu Q., Han J., Chen X., Min Y., . A novel combination approach for the preparation of superhydrophobic surface on copper and the consequent corrosion resistance. Corros. Sci.. 2016;110:105-113.
[Google Scholar]
Liu Y., Cao H., Chen Y., Chen S., Wang D., . Self-assembled super-hydrophobic multilayer films with corrosion resistance on copper substrate. RSC Adv.. 2016;6(3):2379-2386.
[Google Scholar]
Liu Y., Li S., Wang Y., Wang H., Gao K., Han Z., Ren L., . Superhydrophobic and superoleophobic surface by electrodeposition on magnesium alloy substrate: wettability and corrosion inhibition. J. Colloid Interface Sci.. 2016;478:164-171.
[Google Scholar]
Liu Y., Li S., Zhang J., Liu J., Han Z., Ren L., . Corrosion inhibition of biomimetic super-hydrophobic electrodeposition coatings on copper substrate. Corros. Sci.. 2015;94:190-196.
[Google Scholar]
Liu Y., Li S., Zhang J., Wang Y., Han Z., Ren L., . Fabrication of biomimetic superhydrophobic surface with controlled adhesion by electrodeposition. Chem. Eng. J.. 2014;248:440-447.
[Google Scholar]
Liu Y., Yin X., Zhang J., Yu S., Han Z., Ren L., . A electro-deposition process for fabrication of biomimetic super-hydrophobic surface and its corrosion resistance on magnesium alloy. Electrochim. Acta. 2014;125:395-403.
[Google Scholar]
Liu Y., Zhang J., Li S., Wang Y., Han Z., Ren L., . Fabrication of a superhydrophobic graphene surface with excellent mechanical abrasion and corrosion resistance on an aluminum alloy substrate. RSC Adv.. 2014;4(85):45389-45396.
[Google Scholar]
Lomga J., Varshney P., Nanda D., Satapathy M., Mohapatra S., Kumar A., . Fabrication of durable and regenerable superhydrophobic coatings with excellent self-cleaning and anti-fogging properties for aluminium surfaces. J. Alloy. Compd.. 2017;702:161-170.
[Google Scholar]
Long M., Peng S., Chen J., Yang X., Deng W., . A new replication method for fabricating hierarchical polymer surfaces with robust superhydrophobicity and highly improved oleophobicity. Coll. Surf. A: Physicochem. Eng. Aspects. 2016;507:7-17.
[Google Scholar]
Lu X., Wang Z., Yang X., Xu X., Zhang L., Zhao N., Xu J., . Antifogging and antireflective silica film and its application on solar modules. Surf. Coat. Technol.. 2011;206(6):1490-1494.
[Google Scholar]
Lundgren M., Allan N.L., Cosgrove T., . Modeling of wetting: a study of nanowetting at rough and heterogeneous surfaces. Langmuir. 2007;23(3):1187-1194.
[Google Scholar]
Luo Z., Zhang Z., Hu L., Liu W., Guo Z., Zhang H., Wang W., . Stable bionic superhydrophobic coating surface fabricated by a conventional curing process. Adv. Mater.. 2008;20(5):970-974.
[Google Scholar]
Lv Y., Yu X., Jia J., Tu S.-T., Yan J., Dahlquist E., . Fabrication and characterization of superhydrophobic polypropylene hollow fiber membranes for carbon dioxide absorption. Appl. Energy. 2012;90(1):167-174.
[Google Scholar]
Ma M., Hill R.M., . Superhydrophobic surfaces. Curr. Opin. Colloid Interface Sci.. 2006;11(4):193-202.
[Google Scholar]
Ma M., Hill R.M., Lowery J.L., Fridrikh S.V., Rutledge G.C., . Electrospun poly (styrene-block-dimethylsiloxane) block copolymer fibers exhibiting superhydrophobicity. Langmuir. 2005;21(12):5549-5554.
[Google Scholar]
Ma M., Mao Y., Gupta M., Gleason K.K., Rutledge G.C., . Superhydrophobic fabrics produced by electrospinning and chemical vapor deposition. Macromolecules. 2005;38(23):9742-9748.
[Google Scholar]
Ma Z., Hong Y., Ma L., Su M., . Superhydrophobic membranes with ordered arrays of nanospiked microchannels for water desalination. Langmuir. 2009;25(10):5446-5450.
[Google Scholar]
Mahltig B., Böttcher H., . Modified silica sol coatings for water-repellent textiles. J. Sol-Gel Sci. Technol.. 2003;27(1):43-52.
[Google Scholar]
Maitra T., Antonini C., Auf Der Mauer M., Stamatopoulos C., Tiwari M.K., Poulikakos D., . Hierarchically nanotextured surfaces maintaining superhydrophobicity under severely adverse conditions. Nanoscale. 2014;6(15):8710-8719.
[Google Scholar]
Marmur A., . Wetting on hydrophobic rough surfaces: to be heterogeneous or not to be? Langmuir. 2003;19(20):8343-8348.
[Google Scholar]
Martin S., Bhushan B., . Transparent, wear-resistant, superhydrophobic and superoleophobic poly (dimethylsiloxane)(PDMS) surfaces. J. Colloid Interface Sci.. 2017;488:118-126.
[Google Scholar]
McArthur E.A., Ye T., Cross J.P., Petoud S., Borguet E., . Fluorescence detection of surface-bound intermediates produced from UV photoreactivity of alkylsiloxane SAMs. J. Am. Chem. Soc.. 2004;126(8):2260-2261.
[Google Scholar]
McHale G., Flynn M.R., Newton M.I., . Plastron induced drag reduction and increased slip on a superhydrophobic sphere. Soft Matter. 2011;7(21):10100-10107.
[Google Scholar]
Meuler A.J., Smith J.D., Varanasi K.K., Mabry J.M., McKinley G.H., Cohen R.E., . Relationships between water wettability and ice adhesion. ACS Appl. Mater. Interf.. 2010;2(11):3100-3110.
[Google Scholar]
Mo C., Zheng Y., Wang F., Mo Q., . A simple process for fabricating organic/TiO₂ super-hydrophobic and anti-corrosion coating. Int. J. Electrochem. Sci.. 2015;10(9):7380-7391.
[Google Scholar]
Mohamed A.M., Jafari R., Farzaneh M., . An optimization of superhydrophobic polyvinylidene fluoride/zinc oxide materials using Taguchi method. Appl. Surf. Sci.. 2014;288:229-237.
[Google Scholar]
Mohammadi R., Wassink J., Amirfazli A., . Effect of surfactants on wetting of super-hydrophobic surfaces. Langmuir. 2004;20(22):9657-9662.
[Google Scholar]
Momen G., Farzaneh M., . Facile approach in the development of icephobic hierarchically textured coatings as corrosion barrier. Appl. Surf. Sci.. 2014;299:41-46.
[Google Scholar]
Morra M., Occhiello E., Garbassi F., . Contact angle hysteresis in oxygen plasma treated poly (tetrafluoroethylene) Langmuir. 1989;5(3):872-876.
[Google Scholar]
Nakate U.T., Patil P., Bulakhe R., Lokhande C., Kale S.N., Naushad M., Mane R.S., . Sprayed zinc oxide films: Ultra-violet light-induced reversible surface wettability and platinum-sensitization-assisted improved liquefied petroleum gas response. J. Colloid Interf. Sci.. 2016;480:109-117.
[Google Scholar]
Nicolas M., Guittard F., Géribaldi S., . Synthesis of stable super water-and oil-repellent polythiophene films. Angew. Chem. Int. Ed.. 2006;45(14):2251-2254.
[Google Scholar]
Ning T., Xu W., Lu S., . Fabrication of superhydrophobic surfaces on zinc substrates and their application as effective corrosion barriers. Appl. Surf. Sci.. 2011;258(4):1359-1365.
[Google Scholar]
Ogihara H., Okagaki J., Saji T., . Facile fabrication of colored superhydrophobic coatings by spraying a pigment nanoparticle suspension. Langmuir. 2011;27(15):9069-9072.
[Google Scholar]
Oikawa Y., Minami T., Mayama H., Tsujii K., Fushimi K., Aoki Y., Habazaki H., . Preparation of self-organized porous anodic niobium oxide microcones and their surface wettability. Acta Mater.. 2009;57(13):3941-3946.
[CrossRef] [Google Scholar]
Onda T., Shibuichi S., Satoh N., Tsujii K., . Super-water-repellent fractal surfaces. Langmuir. 1996;12(9):2125-2127.
[Google Scholar]
Ou J., Hu W., Wang Y., Wang F., Xue M., Li W., . Construction and corrosion behaviors of a bilayer superhydrophobic film on copper substrate. Surf. Interface Anal.. 2013;45(3):698-704.
[Google Scholar]
Ou J., Hu W., Xue M., Wang F., Li W., . Superhydrophobic surfaces on light alloy substrates fabricated by a versatile process and their corrosion protection. ACS Appl. Mater. Interf.. 2013;5(8):3101-3107.
[Google Scholar]
Ou J., Liu M., Li W., Wang F., Xue M., Li C., . Corrosion behavior of superhydrophobic surfaces of Ti alloys in NaCl solutions. Appl. Surf. Sci.. 2012;258(10):4724-4728.
[Google Scholar]
Pan Q., Wang M., Wang H., . Separating small amount of water and hydrophobic solvents by novel superhydrophobic copper meshes. Appl. Surf. Sci.. 2008;254(18):6002-6006.
[Google Scholar]
Park B., Hwang W., . A facile fabrication method for corrosion-resistant micro/nanostructures on stainless steel surfaces with tunable wettability. Scr. Mater.. 2016;113:118-121.
[Google Scholar]
Parkin I.P., Palgrave R.G., . Self-cleaning coatings. J. Mater. Chem.. 2005;15(17):1689-1695.
[Google Scholar]
Peng M., Li H., Wu L., Zheng Q., Chen Y., Gu W., . Porous poly (vinylidene fluoride) membrane with highly hydrophobic surface. J. Appl. Polym. Sci.. 2005;98(3):1358-1363.
[Google Scholar]
Peng R., Liang L., Hood Z.D., Boulesbaa A., Puretzky A., Ievlev A.V., Wu Z., . In-Plane Heterojunctions Enable Multiphasic Two-Dimensional (2D) MoS2 Nanosheets As Efficient Photocatalysts for Hydrogen Evolution from Water Reduction. ACS Catal.. 2016;6(10):6723-6729.
[CrossRef] [Google Scholar]
Peng S., Tian D., Yang X., Deng W., . Highly efficient and large-scale fabrication of superhydrophobic alumina surface with strong stability based on self-congregated alumina nanowires. ACS Appl. Mater. Interf.. 2005;6(7):4831-4841.
[Google Scholar]
Pilotek S., Schmidt H.K., . Wettability of microstructured hydrophobic sol-gel coatings. J. Sol-Gel Sci. Technol.. 2003;26(1–3):789-792.
[Google Scholar]
Qing G., Sun T., . Chirality-triggered wettability switching on a smart polymer surface. Adv. Mater.. 2011;23(14):1615-1620.
[Google Scholar]
Qing Y., Yang C., Sun Y., Zheng Y., Wang X., Shang Y., Liu C., . Facile fabrication of superhydrophobic surfaces with corrosion resistance by nanocomposite coating of TiO₂ and polydimethylsiloxane. Colloids Surf., A. 2015;484:471-477.
[Google Scholar]
Qing Y., Yang C., Yu N., Shang Y., Sun Y., Wang L., Liu C., . Superhydrophobic TiO₂/polyvinylidene fluoride composite surface with reversible wettability switching and corrosion resistance. Chem. Eng. J.. 2016;290:37-44.
[Google Scholar]
Qu M., Liu S., He J., Feng J., Yao Y., Hou L., Liu X., . Fabrication of recyclable superhydrophobic materials with self-cleaning and mechanically durable properties on various substrates by quartz sand and polyvinylchloride. RSC Adv.. 2016;6(82):79238-79244.
[Google Scholar]
Radwan A.B., Mohamed A.M., Abdullah A.M., Al-Maadeed M.A., . Corrosion protection of electrospun PVDF-ZnO superhydrophobic coating. Surf. Coat. Technol. 2015
[Google Scholar]
Ragesh P., Anand Ganesh V., Nair S.V., Nair A.S., . A review on 'self-cleaning and multifunctional materials' J. Mater. Chem. A. 2014;2(36):14773-14797.
[CrossRef] [Google Scholar]
Rahmawan Y., Xu L., Yang S., . Self-assembly of nanostructures towards transparent, superhydrophobic surfaces. J. Mater. Chem. A. 2013;1(9):2955-2969.
[Google Scholar]
Rao A.V., Latthe S.S., Mahadik S.A., Kappenstein C., . Mechanically stable and corrosion resistant superhydrophobic sol–gel coatings on copper substrate. Appl. Surf. Sci.. 2011;257(13):5772-5776.
[Google Scholar]
Rao A.V., Latthe S.S., Nadargi D.Y., Hirashima H., Ganesan V., . Preparation of MTMS based transparent superhydrophobic silica films by sol–gel method. J. Coll. Interf. Sci.. 2009;332(2):484-490.
[Google Scholar]
Ren L.-F., Xia F., Shao J., Zhang X., Li J., . Experimental investigation of the effect of electrospinning parameters on properties of superhydrophobic PDMS/PMMA membrane and its application in membrane distillation. Desalination. 2017;404:155-166.
[Google Scholar]
Reyssat M., Yeomans J., Quéré D., . Impalement of fakir drops. EPL (Europhys. Lett.). 2007;81(2):26006.
[Google Scholar]
Richard E., Aruna S., Basu B.J., . Superhydrophobic surfaces fabricated by surface modification of alumina particles. Appl. Surf. Sci.. 2012;258(24):10199-10204.
[Google Scholar]
Rothstein J.P., . Slip on superhydrophobic surfaces. Annu. Rev. Fluid Mech.. 2010;42:89-109.
[Google Scholar]
Roy S., Suresh V.M., Maji T.K., . Self-cleaning MOF: Realization of extreme water repellence in coordination driven self-assembled nanostructures. Chem. Sci.. 2016;7(3):2251-2256.
[Google Scholar]
Ryu J., Kim K., Park J., Hwang B.G., Ko Y., Kim H., Lee S.J., . Nearly perfect durable superhydrophobic surfaces fabricated by a simple one-step plasma treatment. Sci. Rep.. 2017;7(1):1981.
[Google Scholar]
Sanchez C., Arribart H., Guille M.M.G., . Biomimetism and bioinspiration as tools for the design of innovative materials and systems. Nat. Mater.. 2005;4(4):277-288.
[Google Scholar]
Seyfoori A., Mirdamadi S., Seyedraoufi Z.S., Khavandi A., Aliofkhazraei M., . Synthesis of biphasic calcium phosphate containing nanostructured films by micro arc oxidation on magnesium alloy. Mater. Chem. Phys.. 2013;142(1):87-94.
[CrossRef] [Google Scholar]
Shang H., Wang Y., Limmer S., Chou T., Takahashi K., Cao G., . Optically transparent superhydrophobic silica-based films. Thin Solid Films. 2005;472(1):37-43.
[Google Scholar]
Sharifi N., Ettouil F.B., Moreau C., Dolatabadi A., Pugh M., . Engineering surface texture and hierarchical morphology of suspension plasma sprayed TiO₂ coatings to control wetting behavior and superhydrophobic properties. Surf. Coat. Technol.. 2017;329:139-148.
[Google Scholar]
She X., Wu J., Xu H., Mo Z., Lian J., Song Y., Li H., . Enhancing charge density and steering charge unidirectional flow in 2D non-metallic semiconductor-CNTs-metal coupled photocatalyst for solar energy conversion. Appl. Catal. B. 2017;202:112-117.
[CrossRef] [Google Scholar]
She Z., Li Q., Wang Z., Li L., Chen F., Zhou J., . Researching the fabrication of anticorrosion superhydrophobic surface on magnesium alloy and its mechanical stability and durability. Chem. Eng. J.. 2017;228:415-424.
[Google Scholar]
She Z., Li Q., Wang Z., Li L., Chen F., Zhou J., . Novel method for controllable fabrication of a superhydrophobic CuO surface on AZ91D magnesium alloy. ACS Appl. Mater. Interf.. 2012;4(8):4348-4356.
[Google Scholar]
She Z., Li Q., Wang Z., Tan C., Zhou J., Li L., . Highly anticorrosion, self-cleaning superhydrophobic Ni-Co surface fabricated on AZ91D magnesium alloy. Surf. Coat. Technol.. 2013;251:7-14.
[Google Scholar]
Sheu H.-H., Lu C.-E., Lee H.-B., Pu N.-W., Wu P.-F., Hsieh S.-H., Ger M.-D., . Electrodeposition of black chromium–cobalt alloy based on trivalent sulfate electrolyte. J. Taiwan Inst. Chem. Eng. 2015
[Google Scholar]
Shi F., Song Y., Niu J., Xia X., Wang Z., Zhang X., . Facile method to fabricate a large-scale superhydrophobic surface by galvanic cell reaction. Chem. Mater.. 2006;18(5):1365-1368.
[Google Scholar]
Shi F., Wang Z., Zhang X., . Combining a layer-by-layer assembling technique with electrochemical deposition of gold aggregates to mimic the legs of water striders. Adv. Mater.. 2005;17(8):1005-1009.
[Google Scholar]
Shi Y., Yang W., Bai J., Feng X., Wang Y., . Fabrication of flower-like copper film with reversible superhydrophobicity–superhydrophilicity and anticorrosion properties. Surf. Coat. Technol.. 2014;253:148-153.
[Google Scholar]
Shibuichi S., Onda T., Satoh N., Tsujii K., . Super water-repellent surfaces resulting from fractal structure. J. Phys. Chem.. 1996;100(50):19512-19517.
[Google Scholar]
Shibuichi S., Yamamoto T., Onda T., Tsujii K., . Super water-and oil-repellent surfaces resulting from fractal structure. J. Colloid Interface Sci.. 1998;208(1):287-294.
[Google Scholar]
Shin S., Seo J., Han H., Kang S., Kim H., Lee T., . Bio-inspired extreme wetting surfaces for biomedical applications. Materials. 2016;9(2)
[CrossRef] [Google Scholar]
Si Y., Guo Z., Liu W., . A robust epoxy resins @ stearic acid-Mg(OH)2 micronanosheet superhydrophobic omnipotent protective coating for real-life applications. ACS Appl. Mater. Interf.. 2016;8(25):16511-16520.
[Google Scholar]
Simpson J.T., Hunter S.R., Aytug T., . Superhydrophobic materials and coatings: a review. Rep. Prog. Phys.. 2015;78(8)
[CrossRef] [Google Scholar]
Skorb E.V., Shchukin D.G., Möhwald H., Andreeva D.V., . Ultrasound-driven design of metal surface nanofoams. Nanoscale. 2010;2(5):722-727.
[Google Scholar]
Soler R., Salabert J., Sebastián R.M., Vallribera A., Roma N., Ricart S., Molins E., . Highly hydrophobic polyfluorinated azo dyes grafted on surfaces. Chem. Commun.. 2011;47(10):2889-2891.
[Google Scholar]
Song T., Liu Q., Zhang M., Chen R., Takahashi K., Jing X., Wang J., . Multiple sheet-layered super slippery surfaces based on anodic aluminium oxide and its anticorrosion property. RSC Adv.. 2015;5(86):70080-70085.
[Google Scholar]
Song Y.Y., Schmidt-Stein F., Berger S., Schmuki P., . TiO₂ nano test tubes as a self-cleaning platform for high-sensitivity immunoassays. Small. 2010;6(11):1180-1184.
[Google Scholar]
Stoiljkovic A., Agarwal S., . Short electrospun fibers by UV cutting method. Macromol. Mater. Eng.. 2008;293(11):895-899.
[Google Scholar]
Su B., Tian Y., Jiang L., . Bioinspired interfaces with superwettability: from materials to chemistry. J. Am. Chem. Soc.. 2016;138(6):1727-1748.
[CrossRef] [Google Scholar]
Su F., Yao K., . Facile fabrication of superhydrophobic surface with excellent mechanical abrasion and corrosion resistance on copper substrate by a novel method. ACS Appl. Mater. Interf.. 2014;6(11):8762-8770.
[Google Scholar]
Su F., Yao K., Liu C., Huang P., . Rapid fabrication of corrosion resistant and superhydrophobic cobalt coating by a one-step electrodeposition. J. Electrochem. Soc.. 2013;160(11):D593-D599.
[Google Scholar]
Sun Q., Liu H., Chen T., Wei Y., Wei Z., . Facile fabrication of iron-based superhydrophobic surfaces via electric corrosion without bath. Appl. Surf. Sci.. 2016;369:277-287.
[Google Scholar]
Tadanaga K., Kitamuro K., Matsuda A., Minami T., . Formation of superhydrophobic alumina coating films with high transparency on polymer substrates by the sol-gel method. J. Sol-Gel Sci. Technol.. 2003;26(1):705-708.
[Google Scholar]
Tadanaga K., Morinaga J., Minami T., . Formation of superhydrophobic-superhydrophilic pattern on flowerlike alumina thin film by the sol-gel method. J. Sol-Gel Sci. Technol.. 2000;19(1–3):211-214.
[Google Scholar]
Tam J., Palumbo G., Erb U., . Recent advances in superhydrophobic electrodeposits. Materials. 2016;9(3):151.
[Google Scholar]
Tan C., Li Q., Cai P., Yang N., Xi Z., . Fabrication of color-controllable superhydrophobic copper compound coating with decoration performance. Appl. Surf. Sci.. 2015;328:623-631.
[Google Scholar]
Tang M.-K., Huang X.-J., Li X.-W., Huang Z.-Y., Zhang S.-M., Zhang Q.-X., . Fabrication of superhydrophobic surface with superior anticorrosion and great mechanical stability on AA7075 Al alloy via a convenient and efficient approach. Mater. Exp.. 2016;6(2):101-115.
[Google Scholar]
Tang M.-K., Zhang Q.-X., Guo Z., Yu J.-G., Li X.-W., Huang X.-J., . A universal laser marking approach for treating aluminum alloy surfaces with enhanced anticorrosion, hardness and reduced friction. RSC Adv.. 2015;5(23):18057-18066.
[Google Scholar]
Tang M.K., Huang X.J., Guo Z., Yu J.G., Li X.W., Zhang Q.X., . Fabrication of robust and stable superhydrophobic surface by a convenient, low-cost and efficient laser marking approach. Coll. Surf. A: Physicochem. Eng. Aspects. 2016;484:449-456.
[Google Scholar]
Tarwal N., Rajgure A., Inamdar A., Devan R., Kim I., Suryavanshi S., Patil P., . Growth of multifunctional ZnO thin films by spray pyrolysis technique. Sens. Actuators, A. 2013;199:67-73.
[Google Scholar]
Thanawala S.K., Chaudhury M.K., . Surface modification of silicone elastomer using perfluorinated ether. Langmuir. 2000;16(3):1256-1260.
[Google Scholar]
Tian D., Zhang X., Tian Y., Wu Y., Wang X., Zhai J., Jiang L., . Photo-induced water–oil separation based on switchable superhydrophobicity–superhydrophilicity and underwater superoleophobicity of the aligned ZnO nanorod array-coated mesh films. J. Mater. Chem.. 2012;22(37):19652-19657.
[Google Scholar]
Tourkine P., Le Merrer M., Quéré D., . Delayed freezing on water repellent materials. Langmuir. 2009;25(13):7214-7216.
[Google Scholar]
Truesdell R., Mammoli A., Vorobieff P., van Swol F., Brinker C.J., . Drag reduction on a patterned superhydrophobic surface. Phys. Rev. Lett.. 2006;97(4):044504.
[Google Scholar]
Tsujii K., Yamamoto T., Onda T., Shibuichi S., . Super oil-repellent surfaces. Angew. Chem., Int. Ed. Engl.. 1997;36(9):1011-1012.
[Google Scholar]
Tuteja A., Choi W., Ma M., Mabry J.M., Mazzella S.A., Rutledge G.C., Cohen R.E., . Designing superoleophobic surfaces. Science. 2007;318(5856):1618-1622.
[Google Scholar]
Victor J., Facchini D., Erb U., . A low-cost method to produce superhydrophobic polymer surfaces. J. Mater. Sci.. 2012;47(8):3690-3697.
[Google Scholar]
Vrancken R.J., Kusumaatmaja H., Hermans K., Prenen A.M., Pierre-Louis O., Bastiaansen C.W., Broer D.J., . Fully reversible transition from Wenzel to Cassie− Baxter states on corrugated superhydrophobic surfaces. Langmuir. 2009;26(5):3335-3341.
[Google Scholar]
Wang C.-H., Song Y.-Y., Zhao J.-W., Xia X.-H., . Semiconductor supported biomimetic superhydrophobic gold surfaces by the galvanic exchange reaction. Surf. Sci.. 2006;600(4):38-42.
[Google Scholar]
Wang C., Yao T., Wu J., Ma C., Fan Z., Wang Z., Yang B., . Facile approach in fabricating superhydrophobic and superoleophilic surface for water and oil mixture separation. ACS Appl. Mater. Interf.. 2009;1(11):2613-2617.
[Google Scholar]
Wang G., Liu S., Wei S., Liu Y., Lian J., Jiang Q., . Robust superhydrophobic surface on Al substrate with durability, corrosion resistance and ice-phobicity. Scient. Rep.. 2016;6
[Google Scholar]
Wang H., Liu Z., Wang E., Yuan R., Gao D., Zhang X., Zhu Y., . A robust superhydrophobic PVDF composite coating with wear/corrosion-resistance properties. Appl. Surf. Sci.. 2015;332:518-524.
[Google Scholar]
Wang J., Li D., Liu Q., Yin X., Zhang Y., Jing X., Zhang M., . Fabrication of hydrophobic surface with hierarchical structure on Mg alloy and its corrosion resistance. Electrochim. Acta. 2010;55(22):6897-6906.
[Google Scholar]
Wang N., Zhao Y., Jiang L., . Low-cost, thermoresponsive wettability of surfaces: poly (N-isopropylacrylamide)/polystyrene composite films prepared by electrospinning. Macromol. Rapid Commun.. 2008;29(6):485-489.
[Google Scholar]
Wang P., Qiu R., Zhang D., Lin Z., Hou B., . Fabricated super-hydrophobic film with potentiostatic electrolysis method on copper for corrosion protection. Electrochim. Acta. 2010;56(1):517-522.
[Google Scholar]
Wang P., Zhang D., Qiu R., . Liquid/solid contact mode of super-hydrophobic film in aqueous solution and its effect on corrosion resistance. Corros. Sci.. 2012;54:77-84.
[Google Scholar]
Wang P., Zhang D., Qiu R., Hou B., . Super-hydrophobic film prepared on zinc as corrosion barrier. Corros. Sci.. 2011;53(6):2080-2086.
[Google Scholar]
Wang P., Zhang D., Qiu R., Wu J., Wan Y., . Super-hydrophobic film prepared on zinc and its effect on corrosion in simulated marine atmosphere. Corros. Sci.. 2013;69:23-30.
[Google Scholar]
Wang S., Feng L., Jiang L., . One-Step Solution-Immersion Process for the Fabrication of Stable Bionic Superhydrophobic Surfaces. Adv. Mater.. 2006;18(6):767-770.
[Google Scholar]
Wang S., Guo X., Xie Y., Liu L., Yang H., Zhu R., Ding W., . Preparation of superhydrophobic silica film on Mg–Nd–Zn–Zr magnesium alloy with enhanced corrosion resistance by combining micro-arc oxidation and sol–gel method. Surf. Coat. Technol.. 2012;213:192-201.
[Google Scholar]
Wang S., Song Y., Jiang L., . Microscale and nanoscale hierarchical structured mesh films with superhydrophobic and superoleophilic properties induced by long-chain fatty acids. Nanotechnology. 2006;18(1):015103.
[Google Scholar]
Wang W.-K., Zheng M.-L., Chen W.-Q., Jin F., Cao Y.-Y., Zhao Z.-S., Duan X.-M., . Microscale golden candock leaves self-aggregated on a polymer surface: Raman scattering enhancement and superhydrophobicity. Langmuir. 2011;27(7):3249-3253.
[Google Scholar]
Wang X., Shen Y., Xie A., Qiu L., Li S., Wang Y., . Novel structure CuI/PANI nanocomposites with bifunctions: superhydrophobicity and photocatalytic activity. J. Mater. Chem.. 2011;21(26):9641-9646.
[Google Scholar]
Wang X., Zheng Y., Yuan J., Shen J., Hu J., Wang A.J., Niu L., . Porous NiCo diselenide nanosheets arrayed on carbon cloth as promising advanced catalysts used in water splitting. Electrochim. Acta. 2017;225:503-513.
[CrossRef] [Google Scholar]
Wang Y., Chen L., Yu X., Wang Y., Zheng G., . Superb alkaline hydrogen evolution and simultaneous electricity generation by Pt-decorated Ni3N nanosheets. Adv. Energy Mater.. 2017;7(2)
[CrossRef] [Google Scholar]
Wang Y., Wang W., Zhong L., Wang J., Jiang Q., Guo X., . Super-hydrophobic surface on pure magnesium substrate by wet chemical method. Appl. Surf. Sci.. 2010;256(12):3837-3840.
[Google Scholar]
Wen Q., Di J., Jiang L., Yu J., Xu R., . Zeolite-coated mesh film for efficient oil–water separation. Chem. Sci.. 2013;4(2):591-595.
[Google Scholar]
Wen X.-F., Wang K., Pi P.-H., Yang J.-X., Cai Z.-Q., Zhang L.-J., Cheng J., . Organic–inorganic hybrid superhydrophobic surfaces using methyltriethoxysilane and tetraethoxysilane sol–gel derived materials in emulsion. Appl. Surf. Sci.. 2011;258(3):991-998.
[Google Scholar]
Wenzel R.N., . Resistance of solid surfaces to wetting by water. Ind. Eng. Chem.. 1936;28(8):988-994.
[Google Scholar]
Williams S.J., Davies G.J., . Protein–carbohydrate interactions: learning lessons from nature. Trends Biotechnol.. 2001;19(9):356-362.
[Google Scholar]
Woodward I., Schofield W., Roucoules V., Badyal J., . Super-hydrophobic surfaces produced by plasma fluorination of polybutadiene films. Langmuir. 2003;19(8):3432-3438.
[Google Scholar]
Woodward J., Gwin H., Schwartz D., . Contact angles on surfaces with mesoscopic chemical heterogeneity. Langmuir. 2000;16(6):2957-2961.
[Google Scholar]
Wu F., Liang J., Peng Z., Liu B., . Electrochemical deposition and characterization of Zn-Al layered double hydroxides (LDHs) films on magnesium alloy. Appl. Surf. Sci.. 2014;313:834-840.
[Google Scholar]
Wu L.-K., Zhang X.-F., Hu J.-M., . Corrosion protection of mild steel by one-step electrodeposition of superhydrophobic silica film. Corros. Sci.. 2014;85:482-487.
[Google Scholar]
Wu L., Zhang J., Li B., Wang A., . Mechanical- and oil-durable superhydrophobic polyester materials for selective oil absorption and oil/water separation. J. Colloid Interf. Sci.. 2014;413:112-117.
[Google Scholar]
Wu L.K., Hu J.M., Zhang J.Q., . One step sol-gel electrochemistry for the fabrication of superhydrophobic surfaces. J. Mater. Chem. A. 2014;1(46):14471-14475.
[Google Scholar]
Wu W., Wang X., Liu X., Zhou F., . Spray-coated fluorine-free superhydrophobic coatings with easy repairability and applicability. ACS Appl. Mater. Interf.. 2009;1(8):1656-1661.
[Google Scholar]
Wu X., Zheng L., Wu D., . Fabrication of superhydrophobic surfaces from microstructured ZnO-based surfaces via a wet-chemical route. Langmuir. 2005;21(7):2665-2667.
[Google Scholar]
Wu Y., Zhao W., Wang W., Sui W., . Fabricating binary anti-corrosion structures containing superhydrophobic surfaces and sturdy barrier layers for Al alloys. RSC Adv.. 2016;6(6):5100-5110.
[Google Scholar]
Xiao J., Lv Q., Zhang Y., Zhang Z., Wang S., . One-step synthesis of nickel phosphide nanowire array supported on nickel foam with enhanced electrocatalytic water splitting performance. RSC Adv.. 2016;6(109):107859-107864.
[CrossRef] [Google Scholar]
Xiu Y., Liu Y., Hess D.W., Wong C., . Mechanically robust superhydrophobicity on hierarchically structured Si surfaces. Nanotechnology. 2010;21(15):155705.
[Google Scholar]
Xu F., Zhang Y., Sun Y., Shi Y., Wen Z., Li Z., . Silver nanoparticles coated zinc oxide nanorods array as superhydrophobic substrate for the amplified SERS effect. J. Phys. Chem. C. 2011;115(20):9977-9983.
[Google Scholar]
Xu N., Sarkar D., Chen X.-G., Tong W., . Corrosion performance of superhydrophobic nickel stearate/nickel hydroxide thin films on aluminum alloy by a simple one-step electrodeposition process. Surf. Coat. Technol.. 2016;302:173-184.
[Google Scholar]
Xu Q., Zhao Q., Zhu X., Cheng L., Bai S., Wang Z., Qin Y., . A new kind of transparent and self-cleaning film for solar cells. Nanoscale. 2016;8(41):17747-17751.
[Google Scholar]
Xu W., Shi X., Lu S., . Controlled growth of superhydrophobic films without any low-surface-energy modification by chemical displacement on zinc substrates. Mater. Chem. Phys.. 2011;129(3):1042-1046.
[Google Scholar]
Xu W., Song J., Sun J., Lu Y., Yu Z., . Rapid fabrication of large-area, corrosion-resistant superhydrophobic Mg alloy surfaces. ACS Appl. Mater. Interf.. 2011;3(11):4404-4414.
[Google Scholar]
Xu X., Zhang Z., Guo F., Yang J., Zhu X., Zhou X., Xue Q., . Superamphiphobic self-assembled monolayer of thiol on the structured Zn surface. Coll. Surf. A: Physicochem. Eng. Aspects. 2012;396:90-95.
[Google Scholar]
Xu X., Zhang Z., Yang J., . Fabrication of biomimetic superhydrophobic surface on engineering materials by a simple electroless galvanic deposition method. Langmuir. 2009;26(5):3654-3658.
[Google Scholar]
Xu X.H., Zhang Z.Z., Yang J., Zhu X., . Study of the corrosion resistance and loading capacity of superhydrophobic meshes fabricated by spraying method. Colloids Surf., A. 2011;377(1):70-75.
[Google Scholar]
Xue L., Li J., Fu J., Han Y., . Super-hydrophobicity of silica nanoparticles modified with vinyl groups. Colloids Surf., A. 2009;338(1):15-19.
[Google Scholar]
Yan H., Kurogi K., Mayama H., Tsujii K., . Environmentally stable super water-repellent poly (alkylpyrrole) films. Angew. Chem. Int. Ed.. 2005;44(22):3453-3456.
[Google Scholar]
Yang H., Pi P., Cai Z.-Q., Wen X., Wang X., Cheng J., Yang Z.-R., . Facile preparation of super-hydrophobic and super-oleophilic silica film on stainless steel mesh via sol–gel process. Appl. Surf. Sci.. 2010;256(13):4095-4102.
[Google Scholar]
Yang N., Li J., Bai N., Xu L., Li Q., . One step phase separation process to fabricate superhydrophobic PVC films and its corrosion prevention for AZ91D magnesium alloy. Mater. Sci. Eng., B. 2016;209:1-9.
[Google Scholar]
Yang N., Li Q., Chen F., Cai P., Tan C., Xi Z., . A solving-reprecipitation theory for self-healing functionality of stannate coating with a high environmental stability. Electrochim. Acta. 2015;174:1192-1201.
[Google Scholar]
Yang Q., He Y., Fan Y., Li F., Chen X., . Exfoliation of the defect-rich MoS2 nanosheets to obtain nanodots modified MoS2 thin nanosheets for electrocatalytic hydrogen evolution. J. Mater. Sci.: Mater. Electron.. 2017;1–6
[CrossRef] [Google Scholar]
Yao L., He J., . Recent progress in antireflection and self-cleaning technology–From surface engineering to functional surfaces. Prog. Mater Sci.. 2014;61:94-143.
[Google Scholar]
Ye J., Yin Q., Zhou Y., . Superhydrophilicity of anodic aluminum oxide films: From “honeycomb” to “bird's nest”. Thin Solid Films. 2009;517(21):6012-6015.
[Google Scholar]
Yin B., Fang L., Hu J., Tang A., He J., Mao J., . A facile method for fabrication of superhydrophobic coating on aluminum alloy. Surf. Interface Anal.. 2012;44(4):439-444.
[Google Scholar]
Yin B., Fang L., Tang A.-Q., Huang Q.-L., Hu J., Mao J.-H., Bai H., . Novel strategy in increasing stability and corrosion resistance for super-hydrophobic coating on aluminum alloy surfaces. Appl. Surf. Sci.. 2011;258(1):580-585.
[Google Scholar]
Yin L., Wang Y., Ding J., Wang Q., Chen Q., . Water condensation on superhydrophobic aluminum surfaces with different low-surface-energy coatings. Appl. Surf. Sci.. 2012;258(8):4063-4068.
[Google Scholar]
Yohe S.T., Colson Y.L., Grinstaff M.W., . Superhydrophobic materials for tunable drug release: using displacement of air to control delivery rates. J. Am. Chem. Soc.. 2012;134(4):2016-2019.
[Google Scholar]
You J.-H., Lee B.-I., Lee J., Kim H., Byeon S.-H., . Superhydrophilic and antireflective La (OH) 3/SiO 2-nanorod/nanosphere films. J. Coll. Interf. Sci.. 2011;354(1):373-379.
[Google Scholar]
Young T., . An essay on the cohesion of fluids. Philos. Trans. R. Soc. Lond.. 1805;95:65-87.
[Google Scholar]
Youngblood J.P., McCarthy T.J., . Ultrahydrophobic polymer surfaces prepared by simultaneous ablation of polypropylene and sputtering of poly (tetrafluoroethylene) using radio frequency plasma. Macromolecules. 1999;32(20):6800-6806.
[Google Scholar]
Yu M., Gu G., Meng W.-D., Qing F.-L., . Superhydrophobic cotton fabric coating based on a complex layer of silica nanoparticles and perfluorooctylated quaternary ammonium silane coupling agent. Appl. Surf. Sci.. 2007;253(7):3669-3673.
[Google Scholar]
Yu X., Wang Z., Jiang Y., Shi F., Zhang X., . Reversible pH-responsive surface: from superhydrophobicity to superhydrophilicity. Adv. Mater.. 2005;17(10):1289-1293.
[Google Scholar]
Yu X., Wang Z., Jiang Y., Zhang X., . Surface gradient material: from superhydrophobicity to superhydrophilicity. Langmuir. 2006;22(10):4483-4486.
[Google Scholar]
Yuan S., Pehkonen S., Liang B., Ting Y., Neoh K., Kang E., . Superhydrophobic fluoropolymer-modified copper surface via surface graft polymerisation for corrosion protection. Corr. Sci.. 2011;53(9):2738-2747.
[Google Scholar]
Yuan Y., Lee T.R., . Contact Angle and Wetting Properties Surface Science Techniques. Springer; 2013. (pp. 3–34)
Yue W.-W., Li H.-J., Xiang T., Qin H., Sun S.-D., Zhao C.-S., . Grafting of zwitterion from polysulfone membrane via surface-initiated ATRP with enhanced antifouling property and biocompatibility. J. Membr. Sci.. 2013;446:79-91.
[Google Scholar]
Yung C.S., Tomlin N.A., Heuerman K., Keller M.W., White M.G., Stephens M., Lehman J.H., . Plasma modification of vertically aligned carbon nanotubes: Superhydrophobic surfaces with ultra-low reflectance. Carbon. 2018;127:195-201.
[Google Scholar]
Zeng C., Wang H., Zhou H., Lin T., . Self-cleaning, superhydrophobic cotton fabrics with excellent washing durability, solvent resistance and chemical stability prepared from an SU-8 derived surface coating. RSC Adv.. 2015;5(75):61044-61050.
[Google Scholar]
Zhai L., Berg M.C., Cebeci F.C., Kim Y., Milwid J.M., Rubner M.F., Cohen R.E., . Patterned superhydrophobic surfaces: toward a synthetic mimic of the Namib Desert beetle. Nano Lett.. 2006;6(6):1213-1217.
[Google Scholar]
Zhang B., Feng H., Lin F., Wang Y., Wang L., Dong Y., Li W., . Superhydrophobic surface fabricated on iron substrate by black chromium electrodeposition and its corrosion resistance property. Appl. Surf. Sci.. 2016;378:388-396.
[Google Scholar]
Zhang B., Li Y., Hou B., . One-step electrodeposition fabrication of a superhydrophobic surface on an aluminum substrate with enhanced self-cleaning and anticorrosion properties. RSC Adv.. 2015;5(121):100000-100010.
[Google Scholar]
Zhang B., Lu S., Xu W., Cheng Y., . Controllable wettability and morphology of electrodeposited surfaces on zinc substrates. Appl. Surf. Sci.. 2016;360:904-914.
[Google Scholar]
Zhang B., Zhao X., Li Y., Hou B., . Fabrication of durable anticorrosion superhydrophobic surfaces on aluminum substrates via a facile one-step electrodeposition approach. RSC Adv.. 2016;6(42):35455-35465.
[Google Scholar]
Zhang D.-Q., Cai Q.-R., He X.-M., Gao L.-X., Kim G.S., . The corrosion inhibition of copper in hydrochloric acid solutions by a tripeptide compound. Corros. Sci.. 2009;51(10):2349-2354.
[Google Scholar]
Zhang F., Chen S., Dong L., Lei Y., Liu T., Yin Y., . Preparation of superhydrophobic films on titanium as effective corrosion barriers. Appl. Surf. Sci.. 2011;257(7):2587-2591.
[Google Scholar]
Zhang F., Zhang C., Song L., Zeng R., Li S., Cui H., . Fabrication of the superhydrophobic surface on magnesium alloy and its corrosion resistance. J. Mater. Sci. Technol.. 2015;31(11):1139-1143.
[Google Scholar]
Zhang F., Zhang C., Zeng R., Song L., Guo L., Huang X., . Corrosion resistance of the superhydrophobic Mg (OH) 2/Mg-Al layered double hydroxide coatings on magnesium alloys. Metals. 2016;6(4):85.
[Google Scholar]
Zhang F., Zhao L., Chen H., Xu S., Evans D.G., Duan X., . Corrosion resistance of superhydrophobic layered double hydroxide films on aluminum. Angew. Chem. Int. Ed.. 2008;47(13):2466-2469.
[Google Scholar]
Zhang H., Yang J., Chen B., Liu C., Zhang M., Li C., . Fabrication of superhydrophobic textured steel surface for anti-corrosion and tribological properties. Appl. Surf. Sci.. 2015;359:905-910.
[Google Scholar]
Zhang H., Yin L., Shi S., Liu X., Wang Y., Wang F., . Facile and fast fabrication method for mechanically robust superhydrophobic surface on aluminum foil. Microelectron. Eng.. 2015;141:238-242.
[Google Scholar]
Zhang J.J., Sui X.L., Huang G.S., Gu D.M., Wang Z.B., . Hierarchical carbon coated molybdenum dioxide nanotubes as a highly active and durable electrocatalytic support for methanol oxidation. J. Mater. Chem. A. 2017;5(8):4067-4074.
[CrossRef] [Google Scholar]
Zhang Q., Wang Y., Wang Y., Al-Enizi A.M., Elzatahry A.A., Zheng G., . Myriophyllum -like hierarchical TiN@Ni3N nanowire arrays for bifunctional water splitting catalysts. J. Mater. Chem. A. 2016;4(15):5713-5718.
[CrossRef] [Google Scholar]
Zhang Q., Xia F., Sun T., Song W., Zhao T., Liu M., Jiang L., . Wettability switching between high hydrophilicity at low pH and high hydrophobicity at high pH on surface based on pH-responsive polymer. Chem. Commun.. 2008;10:1199-1201.
[Google Scholar]
Zhang W., Wang S., Yu X., Zhang Y., . Fabrication of non-modified metallic superhydrophobic surfaces with temperature insensitivity and self-healing ability. Appl. Phys. Lett.. 2016;109(4)
[CrossRef] [Google Scholar]
Zhang X., Shi F., Niu J., Jiang Y., Wang Z., . Superhydrophobic surfaces: from structural control to functional application. J. Mater. Chem.. 2008;18(6):621-633.
[Google Scholar]
Zhang Y., Chen X., Huang Y., Zhang C., Li F., Shu H., . The role of intrinsic defects in electrocatalytic activity of monolayer VS2 basal planes for the hydrogen evolution reaction. J. Phys. Chem. C. 2017;121(3):1530-1536.
[CrossRef] [Google Scholar]
Zhang Z., Ge B., Men X., Li Y., . Mechanically durable, superhydrophobic coatings prepared by dual-layer method for anti-corrosion and self-cleaning. Colloids Surf., A. 2016;490:182-188.
[Google Scholar]
Zhao K., Liu K., Li J., Wang W., Jiang L., . Superamphiphobic CaLi-based bulk metallic glasses. Scripta materialia. 2009;60(4):225-227.
[Google Scholar]
Zhao L., Hong C., Lin L., Wu H., Su Y., Zhang X., Liu A., . Controllable nanoscale engineering of vertically aligned MoS2 ultrathin nanosheets by nitrogen doping of 3D graphene hydrogel for improved electrocatalytic hydrogen evolution. Carbon. 2017;116:223-231.
[CrossRef] [Google Scholar]
Zhao L., Liu Q., Gao R., Wang J., Yang W., Liu L., . One-step method for the fabrication of superhydrophobic surface on magnesium alloy and its corrosion protection, antifouling performance. Corros. Sci.. 2014;80:177-183.
[CrossRef] [Google Scholar]
Zhao N., Shi F., Wang Z., Zhang X., . Combining layer-by-layer assembly with electrodeposition of silver aggregates for fabricating superhydrophobic surfaces. Langmuir. 2005;21(10):4713-4716.
[Google Scholar]
Zhao N., Xie Q., Weng L., Wang S., Zhang X., Xu J., . Superhydrophobic surface from vapor-induced phase separation of copolymer micellar solution. Macromolecules. 2005;38(22):8996-8999.
[Google Scholar]
Zhao Y., Xu Z., Wang X., Lin T., . Photoreactive azido-containing silica nanoparticle/polycation multilayers: durable superhydrophobic coating on cotton fabrics. Langmuir. 2012;28(15):6328-6335.
[Google Scholar]
Zheludkevich M., Poznyak S., Rodrigues L., Raps D., Hack T., Dick L., Ferreira M., . Active protection coatings with layered double hydroxide nanocontainers of corrosion inhibitor. Corros. Sci.. 2010;52(2):602-611.
[Google Scholar]
Zheng S., Li C., Fu Q., Hu W., Xiang T., Wang Q., Chen Z., . Development of stable superhydrophobic coatings on aluminum surface for corrosion-resistant, self-cleaning, and anti-icing applications. Mater. Des.. 2016;93:261-270.
[Google Scholar]
Zheng S., Li C., Fu Q., Li M., Hu W., Wang Q., Chen Z., . Fabrication of self-cleaning superhydrophobic surface on aluminum alloys with excellent corrosion resistance. Surf. Coat. Technol.. 2015;276:341-348.
[Google Scholar]
Zhou M., Pang X., Wei L., Gao K., . Insitu grown superhydrophobic Zn–Al layered double hydroxides films on magnesium alloy to improve corrosion properties. Appl. Surf. Sci.. 2015;337:172-177.
[Google Scholar]
Zhou Y., Xiao H., Wang S., Pan X., Wang Z., An C., Zhang J., . Synthesis of layer-expanded MoS2 nanosheets/carbon fibers nanocomposites for electrochemical hydrogen evolution reaction. Mater. Chem. Phys.. 2016;183:18-23.
[CrossRef] [Google Scholar]
Zhu H., Chen D., Li N., Xu Q., Li H., He J., Lu J., . Dual-layer copper mesh for integrated oil-Water separation and water purification. Appl. Catal. B. 2017;200:594-600.
[Google Scholar]
Zhu X., Zhang Z., Men X., Yang J., Wang K., Xu X., Xue Q., . Robust superhydrophobic surfaces with mechanical durability and easy repairability. J. Mater. Chem.. 2011;21(39):15793-15797.
[Google Scholar]
Zhu X., Zhang Z., Ren G., Men X., Ge B., Zhou X., . Designing transparent superamphiphobic coatings directed by carbon nanotubes. J. Colloid Interf. Sci.. 2014;421:141-145.
[Google Scholar]
Zhu X., Zhang Z., Yang J., Xu X., Men X., Zhou X., . Facile fabrication of a superhydrophobic fabric with mechanical stability and easy-repairability. J. Colloid Interf. Sci.. 2012;380(1):182-186.
[Google Scholar]
Zimmermann J., Reifler F.A., Fortunato G., Gerhardt L.C., Seeger S., . A simple, one-step approach to durable and robust superhydrophobic textiles. Adv. Funct. Mater.. 2008;18(22):3662-3669.
[Google Scholar]
Zou, L., Lan, C., Li, X., Zhang, S., Qiu, Y., Ma, Y. Superhydrophobization of cotton fabric with multiwalled carbon nanotubes for durable electromagnetic interference shielding. Fibers Polym. 16(10), 2158–2164.
Zou W., Zhang L., Liu L., Wang X., Sun J., Wu S., Dong L., . Engineering the Cu₂O–reduced graphene oxide interface to enhance photocatalytic degradation of organic pollutants under visible light. Appl. Catal. B. 2016;181:495-503.
[Google Scholar]

Introduction

Wetting phenomena

Wettability
Requirements for fabrication of SHS
Wetting models
Rolling angle and the wetting angle hysteresis

Application of superhydrophobic surfaces

Increase of corrosion resistance
Anti-fogging surfaces
Anti-bacterial surfaces
Anti-icing surfaces
Oil and water separation
Self-cleaning surfaces
Drag reduction
Battery manufacture technology
Sensors
Water purification
Optical devices
Membrane distillation and water desalination
Microfluidic devices
Other applications

Fabrication of SHS

Sol-gel method
Electrospinning
Electrochemical methods
Layer-by-layer method
Plasma techniques
Other important methods

Corrosion resistance of SHS

Electrodeposition method
Chemical fabrication methods
Sol-gel fabrication method
Spray coating fabrication method
Hydrothermal synthesis fabrication method
Electrospinning fabrication method
Laser operations fabrication method
Methods based on anodic oxidation
Plasma techniques
Other fabrication methods

Chemical stability

The necessity of chemical stability investigation
Chemical stability fading mechanisms
Chemical stability evaluation
Chemical stability improvement approaches

Mechanical stability

Necessity of mechanical stability
Fading mechanism of superhydrophobicity due to mechanical contacts
Important approaches for improvement of mechanical stability

Concluding remarks and future trends

Fulltext Views
7,444

PDF downloads
1,080

View/Download PDF
Download Citations

BibTeX
RIS

Show Sections

[1] Abramov A.A., Vasiliev A.N., Dubovaya O.V., Kovalev V.V., Vatsouro I.M., . Extraction of americium (III), plutonium (IV, V) and neptunium (V) with calixarenes. Mendeleev Commun.. 2012;22(5):260-262.
[Google Scholar]

[2] Acatay K., Simsek E., Ow-Yang C., Menceloglu Y.Z., . Tunable, superhydrophobically stable polymeric surfaces by electrospinning. Angew. Chem. Int. Ed.. 2004;43(39):5210-5213.
[Google Scholar]

[3] Akram Raza M., Kooij E.S., van Silfhout A., Poelsema B., . Superhydrophobic surfaces by anomalous fluoroalkylsilane self-assembly on silica nanosphere arrays. Langmuir. 2010;26(15):12962-12972.
[Google Scholar]

[4] Aliofkhazraei M., Sabour Rouhaghdam A., Shahrabi T., . Abrasive wear behaviour of Si₃N₄/TiO₂ nanocomposite coatings fabricated by plasma electrolytic oxidation. Surf. Coat. Technol.. 2010;205(Supplement 1):S41-S46.
[CrossRef] [Google Scholar]

[5] Andreeva N., Ishizaki T., Baroch P., Saito N., . High sensitive detection of volatile organic compounds using superhydrophobic quartz crystal microbalance. Sens. Actuators, B. 2012;164(1):15-21.
[Google Scholar]

[6] Bagheri H., Aliofkhazraei M., Forooshani H.M., Rouhaghdam A.S., . Electrodeposition of the hierarchical dual structured (HDS) nanocrystalline Ni surface with high water repellency and self-cleaning properties. J. Taiwan Inst. Chem. Eng.. 2017;80:883-893.
[Google Scholar]

[7] Bagheri H., Aliofkhazraei M., Forooshani H.M., Rouhaghdam A.S., . Facile fabrication of uniform hierarchical structured (UHS) nanocomposite surface with high water repellency and self-cleaning properties. Appl. Surf. Sci.. 2018;436:1134-1146.
[Google Scholar]

[8] Bao B., Sun J., Gao M., Zhang X., Jiang L., Song Y., . Patterning liquids on inkjet-imprinted surfaces with highly adhesive superhydrophobicity. Nanoscale. 2016;8(18):9556-9562.
[Google Scholar]

[9] Barkhudarov P.M., Shah P.B., Watkins E.B., Doshi D.A., Brinker C.J., Majewski J., . Corrosion inhibition using superhydrophobic films. Corros. Sci.. 2008;50(3):897-902.
[Google Scholar]

[10] Barshilia H.C., Chaudhary A., Kumar P., Manikandanath N.T., . Wettability of Y₂O₃: a relative analysis of thermally oxidized, reactively sputtered and template assisted nanostructured coatings. Nanomaterials. 2012;2(1):65-78.
[Google Scholar]

[11] Blossey R., . Self-cleaning surfaces—virtual realities. Nature Mater.. 2003;2(5):301-306.
[Google Scholar]

[12] Boinovich L., Emelyanenko A., . A wetting experiment as a tool to study the physicochemical processes accompanying the contact of hydrophobic and superhydrophobic materials with aqueous media. Adv. Colloid Interface Sci.. 2012;179:133-141.
[Google Scholar]

[13] Bormashenko E., Bormashenko Y., . Non-stick droplet surgery with a superhydrophobic scalpel. Langmuir. 2011;27(7):3266-3270.
[Google Scholar]

[14] Bravo J., Zhai L., Wu Z., Cohen R.E., Rubner M.F., . Transparent superhydrophobic films based on silica nanoparticles. Langmuir. 2007;23(13):7293-7298.
[Google Scholar]

[15] Cai P., Bai N., Xu L., Tan C., Li Q., . Fabrication of superhydrophobic wood surface with enhanced environmental adaptability through a solution-immersion process. Surf. Coat. Technol.. 2015;277:262-269.
[Google Scholar]

[16] Cao H., Zheng H., Liu K., Fu R., . Single-crystalline semiconductor In (OH) 3 nanocubes with bifunctions: superhydrophobicity and photocatalytic activity. Cryst. Growth Des.. 2009;10(2):597-601.
[Google Scholar]

[17] Carotenuto G., Martorana B., Perlo P., Nicolais L., . A universal method for the synthesis of metal and metal sulfide clusters embedded in polymer matrices. J. Mater. Chem.. 2003;13(12):2927-2930.
[Google Scholar]

[18] Cassie A., Baxter S., . Wettability of porous surfaces. Trans. Faraday Soc.. 1944;40:546-551.
[Google Scholar]

[19] Chakrabarty S., Nisenholt M., Wynne K.J., . PDMS–fluorous polyoxetane–PDMS triblock hybrid elastomers: tough and transparent with novel bulk morphologies. Macromolecules. 2012;45(19):7900-7913.
[Google Scholar]

[20] Chen W., McCarthy T.J., . Layer-by-layer deposition: a tool for polymer surface modification. Macromolecules. 1997;30(1):78-86.
[Google Scholar]

[21] Chen X., Gong Y., Li D., Li H., . Robust and easy-repairable superhydrophobic surfaces with multiple length-scale topography constructed by thermal spray route. Colloids Surf., A. 2016;492:19-25.
[Google Scholar]

[22] Chen X., Yuan J., Huang J., Ren K., Liu Y., Lu S., Li H., . Large-scale fabrication of superhydrophobic polyurethane/nano-Al 2 O 3 coatings by suspension flame spraying for anti-corrosion applications. Appl. Surf. Sci.. 2014;311:864-869.
[Google Scholar]

[23] Chen Z., Hao L., Chen A., Song Q., Chen C., . A rapid one-step process for fabrication of superhydrophobic surface by electrodeposition method. Electrochim. Acta. 2012;59:168-171.
[Google Scholar]

[24] Cheng Y., Lu S., Xu W., . Controllable wettability of micro-and nano-dendritic structures formed on aluminum substrates. New J. Chem.. 2015;39(8):6602-6610.
[Google Scholar]

[25] Cheng Y., Lu S., Xu W., Wen H., . Fabrication of Au–AlAu 4–Al₂O₃ superhydrophobic surface and its corrosion resistance. RSC Adv.. 2015;5(20):15387-15394.
[Google Scholar]

[26] Cho D.J., Kim S.E., Seo E., Lee M.C., Lee J.M., Ko J.S., . Underwater micro gas detector. Sens. Actuators, B. 2013;188:347-353.
[Google Scholar]

[27] Choi J.H., Kim Y.M., Park Y.W., Park T.H., Dong K.Y., Ju B.K., . Hydrophilic dots on hydrophobic nanopatterned surfaces as a flexible gas barrier. Langmuir. 2009;25(12):7156-7160.
[Google Scholar]

[28] Chu Z., Seeger S., . Superamphiphobic surfaces. Chem. Soc. Rev.. 2014;43(8):2784-2798.
[CrossRef] [Google Scholar]

[29] Cote C., Rosas O., Basseguy R., . Geobacter sulfurreducens: An iron reducing bacterium that can protect carbon steel against corrosion? Corros. Sci.. 2015;94:104-113.
[Google Scholar]

[30] Coulson S., Woodward I., Badyal J., Brewer S., Willis C., . Super-repellent composite fluoropolymer surfaces. J. Phys. Chem. B. 2000;104(37):8836-8840.
[Google Scholar]

[31] Crick C.R., Bear J.C., Southern P., Parkin I.P., . A general method for the incorporation of nanoparticles into superhydrophobic films by aerosol assisted chemical vapour deposition. J. Mater. Chem. A. 2013;1(13):4336-4344.
[Google Scholar]

[32] Cui L.-Y., Liu H.-P., Zhang W.-L., Han Z.-Z., Deng M.-X., Zeng R.-C., Wang Z.-L., . Corrosion resistance of a superhydrophobic micro-arc oxidation coating on Mg-4Li-1Ca alloy. J. Mater. Sci. Technol. 2017
[Google Scholar]

[33] Cui X.-J., Lin X.-Z., Liu C.-H., Yang R.-S., Zheng X.-W., Gong M., . Fabrication and corrosion resistance of a hydrophobic micro-arc oxidation coating on AZ31 Mg alloy. Corros. Sci.. 2015;90:402-412.
[Google Scholar]

[34] Cui Z., Zhang F., Wang L., Xu S., Guo X., . In situ crystallized zirconium phenylphosphonate films with crystals vertically to the substrate and their hydrophobic, dielectric, and anticorrosion properties. Langmuir. 2009;26(1):179-182.
[Google Scholar]

[35] Darband G.B., Aliofkhazraei M., Hamghalam P., Valizade N., . Plasma electrolytic oxidation of magnesium and its alloys: mechanism, properties and applications. J. Magnes. Alloys 2017
[Google Scholar]

[36] Darmanin T., De Givenchy E.T., Amigoni S., Guittard F., . Superhydrophobic surfaces by electrochemical processes. Adv. Mater.. 2013;25(10):1378-1394.
[Google Scholar]

[37] Darmanin T., Guittard F., . Recent advances in the potential applications of bioinspired superhydrophobic materials. J. Mater. Chem. A. 2014;2(39):16319-16359.
[Google Scholar]

[38] Darmanin T., Tarrade J., Celia E., Bellanger H., Guittard F., . Superoleophobic meshes with relatively low hysteresis and sliding angles by electropolymerization: importance of polymer-growth control. ChemPlusChem. 2014;79(3):382-386.
[Google Scholar]

[39] Darmanin T., Tarrade J., Celia E., Guittard F.d.r., . Superoleophobic meshes with high adhesion by electrodeposition of conducting polymer containing short perfluorobutyl chains. J. Phys. Chem. C. 2014;118(4):2052-2057.
[Google Scholar]

[40] Deng X., Mammen L., Zhao Y., Lellig P., Müllen K., Li C., Vollmer D., . Transparent, thermally stable and mechanically robust superhydrophobic surfaces made from porous silica capsules. Adv. Mater.. 2011;23(26):2962-2965.
[Google Scholar]

[41] Dong H., Ye P., Zhong M., Pietrasik J., Drumright R., Matyjaszewski K., . Superhydrophilic surfaces via polymer− SiO₂ nanocomposites. Langmuir. 2010;26(19):15567-15573.
[Google Scholar]

[42] Du X., He J., . A self-templated etching route to surface-rough silica nanoparticles for superhydrophobic coatings. ACS Appl. Mater. Interfaces. 2011;3(4):1269-1276.
[Google Scholar]

[43] Durand N., Mariot D., Améduri B., Boutevin B., Ganachaud F., . Tailored covalent grafting of hexafluoropropylene oxide oligomers onto silica nanoparticles: toward thermally stable, hydrophobic, and oleophobic nanocomposites. Langmuir. 2011;27(7):4057-4067.
[Google Scholar]

[44] Ebert D., Bhushan B., . Transparent, superhydrophobic, and wear-resistant coatings on glass and polymer substrates using SiO₂, ZnO, and ITO nanoparticles. Langmuir. 2012;28(31):11391-11399.
[Google Scholar]

[45] Egorkin V., Vyaliy I., Minaev A., Sinebryukhov S., Gnedenkov S., . Morphological features and electrochemical properties of the hydrophobized sealed PEO-coatings on Al alloy. Solid State Phenom.. 2016;245
[Google Scholar]

[46] Egorkin, V., Vyaliy, I., Sinebryukhov, S., Gnedenkov, S., 2015. Evaluation of electrochemical properties of the PEO-coatings treated with hydrophobic agent solution on aluminium alloy. In: Paper Presented at the Solid State Phenomena.

[47] Emelyanenko A.M., Shagieva F.M., Domantovsky A.G., Boinovich L.B., . Nanosecond laser micro- and nanotexturing for the design of a superhydrophobic coating robust against long-term contact with water, cavitation, and abrasion. Appl. Surf. Sci.. 2015;332:513-517.
[Google Scholar]

[48] Erbil H.Y., Cansoy C.E., . Range of applicability of the Wenzel and Cassie−Baxter equations for superhydrophobic surfaces. Langmuir. 2009;25(24):14135-14145.
[Google Scholar]

[49] Esmailzadeh S., Khorsand S., Raeissi K., Ashrafizadeh F., . Microstructural evolution and corrosion resistance of super-hydrophobic electrodeposited nickel films. Surf. Coat. Technol.. 2015;283:337-346.
[Google Scholar]

[50] Fadeev A.Y., Helmy R., Marcinko S., . Self-assembled monolayers of organosilicon hydrides supported on titanium, zirconium, and hafnium dioxides. Langmuir. 2002;18(20):7521-7529.
[Google Scholar]

[51] Fan M.M., Liu H.F., Dong Z.H., . Microbiologically influenced corrosion of X60 carbon steel in CO₂-saturated oilfield flooding water. Mater. Corros.. 2013;64(3):242-246.
[Google Scholar]

[52] Fan X., Liu Y., Quan X., Zhao H., Chen S., Yi G., Du L., . High desalination permeability, wetting and fouling resistance on superhydrophobic carbon nanotube hollow fiber membrane under self-powered electrochemical assistance. J. Membr. Sci.. 2016;514:501-509.
[Google Scholar]

[53] Fan Y., Chen S., Zhao H., Liu Y., . Distillation membrane constructed by TiO₂ nanofiber followed by fluorination for excellent water desalination performance. Desalination. 2017;405:51-58.
[Google Scholar]

[54] Fan Y., He Y., Luo P., Chen X., Liu B., . A facile electrodeposition process to fabricate corrosion-resistant superhydrophobic surface on carbon steel. Appl. Surf. Sci.. 2016;368:435-442.
[Google Scholar]

[55] Fan Y., Li C., Chen Z., Chen H., . Study on fabrication of the superhydrophobic sol–gel films based on copper wafer and its anti-corrosive properties. Appl. Surf. Sci.. 2012;258(17):6531-6536.
[Google Scholar]

[56] Fang L.J., Li Y.H., Liu P.F., Wang D.P., Zeng H.D., Wang X.L., Yang H.G., . Facile fabrication of large-aspect-ratio g-C₃N₄ nanosheets for enhanced photocatalytic hydrogen evolution. ACS Sustain. Chem. Eng.. 2017;5(3):2039-2043.
[CrossRef] [Google Scholar]

[57] Farhadi S., Aliofkhazraei M., Darband G.B., Abolhasani A., Rouhaghdam A.S., . Corrosion and wettability of PEO coatings on magnesium by addition of potassium stearate. J. Magnes. Alloys. 2017;5(2):210-216.
[Google Scholar]

[58] Farhadi S., Aliofkhazraei M., Darband G.B., Abolhasani A., Rouhaghdam A.S., . Wettability and corrosion behavior of chemically modified plasma electrolytic oxidation nanocomposite coating. J. Mater. Eng. Perform.. 2017;26(10):4797-4806.
[Google Scholar]

[59] Farhadi S.S., . Effect of Fatty Acids Additive in Electrolyte on Wettability of PEO Nanocomposite Coating on Mg, Ti and Al. Tarbiat Modares University; 2014. (MSc)

[60] Feng L., Che Y., Liu Y., Qiang X., Wang Y., . Fabrication of superhydrophobic aluminium alloy surface with excellent corrosion resistance by a facile and environment-friendly method. Appl. Surf. Sci.. 2013;283:367-374.
[Google Scholar]

[61] Feng L., Li S., Li H., Zhai J., Song Y., Jiang L., Zhu D., . Super-hydrophobic surface of aligned polyacrylonitrile nanofibers. Angew. Chem.. 2002;114(7):1269-1271.
[Google Scholar]

[62] Feng L., Yan Z., Qiang X., Liu Y., Wang Y., . Facile formation of superhydrophobic aluminum alloy surface and corrosion-resistant behavior. Appl. Phys. A. 2016;122(3):1-14.
[Google Scholar]

[63] Feng L., Zhang H., Wang Z., Liu Y., . Superhydrophobic aluminum alloy surface: fabrication, structure, and corrosion resistance. Colloids Surf., A. 2014;441:319-325.
[Google Scholar]

[64] Feng L., Zhang Z., Mai Z., Ma Y., Liu B., Jiang L., Zhu D., . A super-hydrophobic and super-oleophilic coating mesh film for the separation of oil and water. Angew. Chem. Int. Ed.. 2004;43(15):2012-2014.
[Google Scholar]

[65] Feng L., Zhu Y., Fan W., Wang Y., Qiang X., Liu Y., . Fabrication and corrosion resistance of superhydrophobic magnesium alloy. Appl. Phys. A. 2015;120(2):561-570.
[Google Scholar]

[66] Forooshani H.M., Aliofkhazraei M., Rouhaghdam A.S., . Superhydrophobic aluminum surfaces by mechanical/chemical combined method and its corrosion behavior. J. Taiwan Inst. Chem. Eng.. 2017;72:220-235.
[Google Scholar]

[67] Gao H., Lu S., Xu W., Szunerits S., Boukherroub R., . Controllable fabrication of stable superhydrophobic surfaces on iron substrates. RSC Adv.. 2015;5(51):40657-40667.
[Google Scholar]

[68] Gao R., Liu Q., Wang J., Zhang X., Yang W., Liu J., Liu L., . Fabrication of fibrous szaibelyite with hierarchical structure superhydrophobic coating on AZ31 magnesium alloy for corrosion protection. Chem. Eng. J.. 2014;241:352-359.
[Google Scholar]

[69] Gao Z., Ma M., Zhai X., Zhang M., Zang D., Wang C., . Improvement of chemical stability and durability of superhydrophobic wood surface via a film of TiO2 coated CaCO3 micro-/nano-composite particles. RSC Adv.. 2015;5(79):63978-63984.
[Google Scholar]

[70] Garrod R., Harris L., Schofield W., McGettrick J., Ward L., Teare D., Badyal J., . Mimicking a stenocara beetle's back for microcondensation using plasmachemical patterned superhydrophobic-superhydrophilic surfaces. Langmuir. 2007;23(2):689-693.
[Google Scholar]

[71] Ge D., Yang L., Wu G., Yang S., . Spray coating of superhydrophobic and angle-independent coloured films. Chem. Commun.. 2014;50(19):2469-2472.
[Google Scholar]

[72] Genzer J., Efimenko K., . Recent developments in superhydrophobic surfaces and their relevance to marine fouling: a review. Biofouling. 2006;22(5):339-360.
[Google Scholar]

[73] Gnedenkov S., Sinebryukhov S., Egorkin V., Mashtalyar D., Alpysbaeva D., Boinovich L., . Wetting and electrochemical properties of hydrophobic and superhydrophobic coatings on titanium. Colloids Surf., A. 2011;383(1):61-66.
[Google Scholar]

[74] Gnedenkov S., Sinebryukhov S., Egorkin V., Mashtalyar D., Emelyanenko A., Boinovich L., . Electrochemical properties of the superhydrophobic coatings on metals and alloys. J. Taiwan Inst. Chem. Eng.. 2014;45(6):3075-3080.
[Google Scholar]

[75] Good R.J., . A thermodynamic derivation of Wenzel's modification of Young's equation for contact angles; together with a theory of hysteresis. J. Am. Chem. Soc.. 1952;74(20):5041-5042.
[Google Scholar]

[76] Goodwyn P.P., Maezono Y., Hosoda N., Fujisaki K., . Waterproof and translucent wings at the same time: problems and solutions in butterflies. Naturwissenschaften. 2009;96(7):781-787.
[Google Scholar]

[77] Grignard B., Vaillant A., de Coninck J., Piens M., Jonas A.M., Detrembleur C., Jerome C., . Electrospinning of a functional perfluorinated block copolymer as a powerful route for imparting superhydrophobicity and corrosion resistance to aluminum substrates. Langmuir. 2010;27(1):335-342.
[Google Scholar]

[78] Gu S.Y., Wang Z.M., Li J.B., Ren J., . Switchable Wettability of Thermo-Responsive Biocompatible Nanofibrous Films Created by Electrospinning. Macromol. Mater. Eng.. 2010;295(1):32-36.
[Google Scholar]

[79] Gui X., Li H., Wang K., Wei J., Jia Y., Li Z., Wu D., . Recyclable carbon nanotube sponges for oil absorption. Acta Mater.. 2011;59(12):4798-4804.
[Google Scholar]

[80] Guo F., Su X., Hou G., Liu Z., Mei Z., . Fabrication of superhydrophobic TiO₂ surface with cactus-like structure by a facile hydrothermal approach. Colloids Surf., A. 2012;395:70-74.
[Google Scholar]

[81] Guo J., Wang L., Wang S., Liang J., Xue Q., Yan F., . Preparation and performance of a novel multifunctional plasma electrolytic oxidation composite coating formed on magnesium alloy. J. Mater. Sci.. 2009;44(8):1998-2006.
[Google Scholar]

[82] Guo M., Kang Z., Li W., Zhang J., . A facile approach to fabricate a stable superhydrophobic film with switchable water adhesion on titanium surface. Surf. Coat. Technol.. 2015;239:227-232.
[Google Scholar]

[83] Guo P., Zhai S., Xiao Z., An Q., . One-step fabrication of highly stable, superhydrophobic composites from controllable and low-cost PMHS/TEOS sols for efficient oil cleanup. J. Colloid Interface Sci.. 2015;446:155-162.
[Google Scholar]

[84] Han J.T., Zheng Y., Cho J.H., Xu X., Cho K., . Stable superhydrophobic organic-inorganic hybrid films by electrostatic self-assembly. J. Phys. Chem. B. 2005;109(44):20773-20778.
[Google Scholar]

[85] Hao J.Y., Wang Y.Y., Tong X.L., Jin G.Q., Guo X.Y., . Photocatalytic hydrogen production over modified SiC nanowires under visible light irradiation. Int. J. Hydrogen Energy. 2012;37(20):15038-15044.
[CrossRef] [Google Scholar]

[86] Hashemzadeh M., Raeissi K., Ashrafizadeh F., Khorsand S., . Effect of ammonium chloride on microstructure, super-hydrophobicity and corrosion resistance of nickel coatings. Surf. Coat. Technol.. 2015;283:318-328.
[Google Scholar]

[87] Hashim N.A., Liu Y., Li K., . Preparation of PVDF hollow fiber membranes using SiO₂ particles: the effect of acid and alkali treatment on the membrane performances. Ind. Eng. Chem. Res.. 2011;50(5):3035-3040.
[Google Scholar]

[88] Hassan A., Wasim A., Jiang X., . Upscaling and its application in numerical simulation of long-term CO₂ storage. Greenh. Gases Sci. Technol.. 2012;2(6):408-418.
[Google Scholar]

[89] He T., Wang Y., Zhang Y., Xu T., Liu T., . Super-hydrophobic surface treatment as corrosion protection for aluminum in seawater. Corros. Sci.. 2009;51(8):1757-1761.
[Google Scholar]

[90] Heinonen S., Huttunen-Saarivirta E., Nikkanen J.P., Raulio M., Priha O., Laakso J., Levänen E., . Antibacterial properties and chemical stability of superhydrophobic silver-containing surface produced by sol-gel route. Colloids Surf. A: Physicochem. Eng. Aspects. 2014;453(1):149-161.
[Google Scholar]

[91] Hench L.L., West J.K., . The sol-gel process. Chem. Rev.. 1990;90(1):33-72.
[Google Scholar]

[92] Hermelin E., Petitjean J., Lacroix J.-C., Chane-Ching K.I., Tanguy J., Lacaze P.-C., . Ultrafast electrosynthesis of high hydrophobic polypyrrole coatings on a zinc electrode: applications to the protection against corrosion. Chem. Mater.. 2008;20(13):4447-4456.
[Google Scholar]

[93] Hikita M., Tanaka K., Nakamura T., Kajiyama T., Takahara A., . Super-liquid-repellent surfaces prepared by colloidal silica nanoparticles covered with fluoroalkyl groups. Langmuir. 2005;21(16):7299-7302.
[Google Scholar]

[94] Hintze P.E., Calle L.M., . Electrochemical properties and corrosion protection of organosilane self-assembled monolayers on aluminum 2024–T3. Electrochim. Acta. 2006;51(8):1761-1766.
[Google Scholar]

[95] Hou W., Kang Z., . Preparation of duplex film through microarc oxidation coloring and polymer plating on Mg-Li alloy and its corrosion resistance. Int. J. Electrochem. Sci.. 2013;8:5613-5620.
[Google Scholar]

[96] Howarter J.A., Youngblood J.P., . Self-cleaning and anti-fog surfaces via stimuli-responsive polymer brushes. Adv. Mater.. 2007;19(22):3838-3843.
[Google Scholar]

[97] Howarter J.A., Youngblood J.P., . Self-cleaning and next generation anti-fog surfaces and coatings. Macromol. Rapid Commun.. 2008;29(6):455-466.
[Google Scholar]

[98] Hu F., Xu P., Wang H., Byoung Kang U., Hu A., Li M., . Superhydrophobic and anti-corrosion Cu microcones/Ni–W alloy coating fabricated by electrochemical approaches. RSC Adv.. 2015;5(126):103863-103868.
[Google Scholar]

[99] Huang Y., Sarkar D.K., Chen X., . Fabrication of corrosion resistance micro-nanostructured superhydrophobic anodized aluminum in a one-step electrodeposition process. Metals. 2016;6(3):47.
[Google Scholar]

[100] Ionov L., Synytska A., . Self-healing superhydrophobic materials. Phys. Chem. Chem. Phys.. 2012;14(30):10497-10502.
[CrossRef] [Google Scholar]

[101] Ishizaki T., Hieda J., Saito N., Saito N., Takai O., . Corrosion resistance and chemical stability of super-hydrophobic film deposited on magnesium alloy AZ31 by microwave plasma-enhanced chemical vapor deposition. Electrochim. Acta. 2010;55(23):7094-7101.
[Google Scholar]

[102] Ishizaki T., Saito N., . Rapid formation of a superhydrophobic surface on a magnesium alloy coated with a cerium oxide film by a simple immersion process at room temperature and its chemical stability. Langmuir. 2010;26(12):9749-9755.
[Google Scholar]

[103] Ishizaki T., Sakamoto M., . Facile formation of biomimetic color-tuned superhydrophobic magnesium alloy with corrosion resistance. Langmuir. 2011;27(6):2375-2381.
[Google Scholar]

[104] Jiang J., Xu J., Liu Z., Deng L., Sun B., Liu S., Liu H., . Preparation, corrosion resistance and hemocompatibility of the superhydrophobic TiO₂ coatings on biomedical Ti-6Al-4V alloys. Appl. Surf. Sci.. 2015;347:591-595.
[Google Scholar]

[105] Jiang Y., Wang Z., Yu X., Shi F., Xu H., Zhang X., Dehaen W., . Self-assembled monolayers of dendron thiols for electrodeposition of gold nanostructures: toward fabrication of superhydrophobic/superhydrophilic surfaces and pH-responsive surfaces. Langmuir. 2005;21(5):1986-1990.
[Google Scholar]

[106] Jie H., Xu Q., Wei L., Min Y., . Etching and heating treatment combined approach for superhydrophobic surface on brass substrates and the consequent corrosion resistance. Corros. Sci.. 2016;102:251-258.
[Google Scholar]

[107] Jitianu A., Doyle J., Amatucci G., Klein L.C., . Methyl modified siloxane melting gels for hydrophobic films. J. Sol-Gel Sci. Technol.. 2010;53(2):272-279.
[Google Scholar]

[108] Jung S., Tiwari M.K., Doan N.V., Poulikakos D., . Mechanism of supercooled droplet freezing on surfaces. Nat. Commun.. 2012;3:615.
[Google Scholar]

[109] Jung Y.C., Bhushan B., . Dynamic effects induced transition of droplets on biomimetic superhydrophobic surfaces. Langmuir. 2009;25(16):9208-9218.
[Google Scholar]

[110] Kang Z., Lai X., Wang F., Long Y., Li Y., . Preparation of super-hydrophobic duplex-treated film on surface of Mg–Mn–Ce magnesium alloy and its corrosion resistance. Chin. J. Nonferr. Met.. 2011;21(2):283-289.
[Google Scholar]

[111] Kavale M.S., Mahadik D., Parale V., Wagh P., Gupta S.C., Rao A.V., Barshilia H.C., . Optically transparent, superhydrophobic methyltrimethoxysilane based silica coatings without silylating reagent. Appl. Surf. Sci.. 2011;258(1):158-162.
[Google Scholar]

[112] Khorsand S., Raeissi K., Ashrafizadeh F., . Corrosion resistance and long-term durability of super-hydrophobic nickel film prepared by electrodeposition process. Appl. Surf. Sci.. 2014;305:498-505.
[Google Scholar]

[113] Khorsand S., Raeissi K., Ashrafizadeh F., Arenas M., Conde A., . Corrosion behaviour of super-hydrophobic electrodeposited nickel–cobalt alloy film. Appl. Surf. Sci.. 2016;364:349-357.
[Google Scholar]

[114] Kim B.R., Kim D.H., Kim Y.D., . Superhydrophobic, flexible and gas-permeable membrane prepared by a simple one-step vapor deposition. Kor. J. Chem. Eng. 2016:1-6.
[Google Scholar]

[115] Koishi T., Yasuoka K., Fujikawa S., Ebisuzaki T., Zeng X.C., . Coexistence and transition between Cassie and Wenzel state on pillared hydrophobic surface. Proc. Natl. Acad. Sci.. 2009;106(21):8435-8440.
[Google Scholar]

[116] Kota A.K., Li Y., Mabry J.M., Tuteja A., . Hierarchically structured superoleophobic surfaces with ultralow contact angle hysteresis. Adv. Mater.. 2012;24(43):5838-5843.
[Google Scholar]

[117] Kulinich S., Farhadi S., Nose K., Du X., . Superhydrophobic surfaces: are they really ice-repellent? Langmuir. 2010;27(1):25-29.
[Google Scholar]

[118] Kulinich S., Farzaneh M., . How wetting hysteresis influences ice adhesion strength on superhydrophobic surfaces. Langmuir. 2009;25(16):8854-8856.
[Google Scholar]

[119] Kulinich S., Farzaneh M., . Ice adhesion on super-hydrophobic surfaces. Appl. Surf. Sci.. 2009;255(18):8153-8157.
[Google Scholar]

[120] Lakshmi R., Bharathidasan T., Basu B.J., . Superhydrophobic sol–gel nanocomposite coatings with enhanced hardness. Appl. Surf. Sci.. 2011;257(24):10421-10426.
[Google Scholar]

[121] Latthe S.S., Sudhagar P., Devadoss A., Kumar A.M., Liu S., Terashima C., Fujishima A., . A mechanically bendable superhydrophobic steel surface with self-cleaning and corrosion-resistant properties. J. Mater. Chem. A. 2015;3(27):14263-14271.
[Google Scholar]

[122] Lee S.-M., Kim K.-S., Pippel E., Kim S., Kim J.-H., Lee H.-J., . Facile route toward mechanically stable superhydrophobic copper using oxidation–reduction induced morphology changes. J. Phys. Chem. C. 2012;116(4):2781-2790.
[Google Scholar]

[123] Li J., Wu R., Jing Z., Yan L., Zha F., Lei Z., . One-step spray-coating process for the fabrication of colorful superhydrophobic coatings with excellent corrosion resistance. Langmuir. 2015;31(39):10702-10707.
[Google Scholar]

[124] Li K., Zeng X., Li H., Lai X., . A study on the fabrication of superhydrophobic iron surfaces by chemical etching and galvanic replacement methods and their anti-icing properties. Appl. Surf. Sci.. 2015;346:458-463.
[Google Scholar]

[125] Li W., Xiong D., Gao X., Song W.G., Xia F., Liu L., . Self-supported Co-Ni-P ternary nanowire electrodes for highly efficient and stable electrocatalytic hydrogen evolution in acidic solution. Catal. Today 2016
[CrossRef] [Google Scholar]

[126] Li Y., Li L., Sun J., . Bioinspired self-healing superhydrophobic coatings. Angew. Chem.. 2010;122(35):6265-6269.
[Google Scholar]

[127] Li Y., Shi G., . Electrochemical growth of two-dimensional gold nanostructures on a thin polypyrrole film modified ITO electrode. J. Phys. Chem. B. 2005;109(50):23787-23793.
[Google Scholar]

[128] Liang J., Hu Y., Fan Y., Chen H., . Formation of superhydrophobic cerium oxide surfaces on aluminum substrate and its corrosion resistance properties. Surf. Interf. Anal.. 2013;45(8):1211-1216.
[Google Scholar]

[129] Liang J., Hu Y., Wu Y., Chen H., . Facile formation of superhydrophobic silica-based surface on aluminum substrate with tetraethylorthosilicate and vinyltriethoxysilane as co-precursor and its corrosion resistant performance in corrosive NaCl aqueous solution. Surf. Coat. Technol.. 2014;240:145-153.
[Google Scholar]

[130] Lifton V.A., Simon S., Frahm R.E., . Reserve battery architecture based on superhydrophobic nanostructured surfaces. Bell Labs Tech. J.. 2005;10(3):81-85.
[Google Scholar]

[131] Lin C.-Y., Lin K.-Y.A., Yang T.-W., Chen Y.-C., Yang H., . Self-assembled hemispherical nanowell arrays for superhydrophobic antireflection coatings. J. Colloid Interface Sci.. 2017;490:174-180.
[Google Scholar]

[132] Lin Y., Shen Y., Liu A., Zhu Y., Liu S., Jiang H., . Bio-inspiredly fabricating the hierarchical 3D porous structure superhydrophobic surfaces for corrosion prevention. Mater. Des.. 2016;103:300-307.
[Google Scholar]

[133] Liu B., Fu Y., Ruan W., He Y., Wang X., . Preparation of super-hydrophobic surfaces by using elastomer templates and UV-curable resins. Acta Poly. Sin.. 2008;2:155.
[Google Scholar]

[134] Liu H., Szunerits S., Xu W., Boukherroub R., . Preparation of superhydrophobic coatings on zinc as effective corrosion barriers. ACS Appl. Mater. Interf.. 2009;1(6):1150-1153.
[Google Scholar]

[135] Liu J., Xiao X., Shi Y., Wan C., . Fabrication of a superhydrophobic surface from porous polymer using phase separation. Appl. Surf. Sci.. 2014;297:33-39.
[Google Scholar]

[136] Liu K., Jiang L., . Multifunctional integration: from biological to bio-inspired materials. ACS Nano. 2011;5(9):6786-6790.
[Google Scholar]

[137] Liu L., Chen R., Liu W., Zhang Y., Shi X., Pan Q., . Fabrication of superhydrophobic copper sulfide film for corrosion protection of copper. Surf. Coat. Technol.. 2015;272:221-228.
[Google Scholar]

[138] Liu M., Wang S., Wei Z., Song Y., Jiang L., . Bioinspired design of a superoleophobic and low adhesive water/solid interface. Adv. Mater.. 2009;21(6):665-669.
[Google Scholar]

[139] Liu Q., Chen D., Kang Z., . One-step electrodeposition process to fabricate corrosion-resistant superhydrophobic surface on magnesium alloy. ACS Appl. Mater. Interf.. 2015;7(3):1859-1867.
[Google Scholar]

[140] Liu Q., Kang Z., . One-step electrodeposition process to fabricate superhydrophobic surface with improved anticorrosion property on magnesium alloy. Mater. Lett.. 2014;137:210-213.
[CrossRef] [Google Scholar]

[141] Liu T., Chen S., Cheng S., Tian J., Chang X., Yin Y., . Corrosion behavior of super-hydrophobic surface on copper in seawater. Electrochim. Acta. 2007;52(28):8003-8007.
[Google Scholar]

[142] Liu T., Yin Y., Chen S., Chang X., Cheng S., . Super-hydrophobic surfaces improve corrosion resistance of copper in seawater. Electrochim. Acta. 2007;52(11):3709-3713.
[Google Scholar]

[143] Liu W., Luo Y., Sun L., Wu R., Jiang H., Liu Y., . Fabrication of the superhydrophobic surface on aluminum alloy by anodizing and polymeric coating. Appl. Surf. Sci.. 2013;264:872-878.
[Google Scholar]

[144] Liu W., Xu Q., Han J., Chen X., Min Y., . A novel combination approach for the preparation of superhydrophobic surface on copper and the consequent corrosion resistance. Corros. Sci.. 2016;110:105-113.
[Google Scholar]

[145] Liu Y., Cao H., Chen Y., Chen S., Wang D., . Self-assembled super-hydrophobic multilayer films with corrosion resistance on copper substrate. RSC Adv.. 2016;6(3):2379-2386.
[Google Scholar]

[146] Liu Y., Li S., Wang Y., Wang H., Gao K., Han Z., Ren L., . Superhydrophobic and superoleophobic surface by electrodeposition on magnesium alloy substrate: wettability and corrosion inhibition. J. Colloid Interface Sci.. 2016;478:164-171.
[Google Scholar]

[147] Liu Y., Li S., Zhang J., Liu J., Han Z., Ren L., . Corrosion inhibition of biomimetic super-hydrophobic electrodeposition coatings on copper substrate. Corros. Sci.. 2015;94:190-196.
[Google Scholar]

[148] Liu Y., Li S., Zhang J., Wang Y., Han Z., Ren L., . Fabrication of biomimetic superhydrophobic surface with controlled adhesion by electrodeposition. Chem. Eng. J.. 2014;248:440-447.
[Google Scholar]

[149] Liu Y., Yin X., Zhang J., Yu S., Han Z., Ren L., . A electro-deposition process for fabrication of biomimetic super-hydrophobic surface and its corrosion resistance on magnesium alloy. Electrochim. Acta. 2014;125:395-403.
[Google Scholar]

[150] Liu Y., Zhang J., Li S., Wang Y., Han Z., Ren L., . Fabrication of a superhydrophobic graphene surface with excellent mechanical abrasion and corrosion resistance on an aluminum alloy substrate. RSC Adv.. 2014;4(85):45389-45396.
[Google Scholar]

[151] Lomga J., Varshney P., Nanda D., Satapathy M., Mohapatra S., Kumar A., . Fabrication of durable and regenerable superhydrophobic coatings with excellent self-cleaning and anti-fogging properties for aluminium surfaces. J. Alloy. Compd.. 2017;702:161-170.
[Google Scholar]

[152] Long M., Peng S., Chen J., Yang X., Deng W., . A new replication method for fabricating hierarchical polymer surfaces with robust superhydrophobicity and highly improved oleophobicity. Coll. Surf. A: Physicochem. Eng. Aspects. 2016;507:7-17.
[Google Scholar]

[153] Lu X., Wang Z., Yang X., Xu X., Zhang L., Zhao N., Xu J., . Antifogging and antireflective silica film and its application on solar modules. Surf. Coat. Technol.. 2011;206(6):1490-1494.
[Google Scholar]

[154] Lundgren M., Allan N.L., Cosgrove T., . Modeling of wetting: a study of nanowetting at rough and heterogeneous surfaces. Langmuir. 2007;23(3):1187-1194.
[Google Scholar]

[155] Luo Z., Zhang Z., Hu L., Liu W., Guo Z., Zhang H., Wang W., . Stable bionic superhydrophobic coating surface fabricated by a conventional curing process. Adv. Mater.. 2008;20(5):970-974.
[Google Scholar]

[156] Lv Y., Yu X., Jia J., Tu S.-T., Yan J., Dahlquist E., . Fabrication and characterization of superhydrophobic polypropylene hollow fiber membranes for carbon dioxide absorption. Appl. Energy. 2012;90(1):167-174.
[Google Scholar]

[157] Ma M., Hill R.M., . Superhydrophobic surfaces. Curr. Opin. Colloid Interface Sci.. 2006;11(4):193-202.
[Google Scholar]

[158] Ma M., Hill R.M., Lowery J.L., Fridrikh S.V., Rutledge G.C., . Electrospun poly (styrene-block-dimethylsiloxane) block copolymer fibers exhibiting superhydrophobicity. Langmuir. 2005;21(12):5549-5554.
[Google Scholar]

[159] Ma M., Mao Y., Gupta M., Gleason K.K., Rutledge G.C., . Superhydrophobic fabrics produced by electrospinning and chemical vapor deposition. Macromolecules. 2005;38(23):9742-9748.
[Google Scholar]

[160] Ma Z., Hong Y., Ma L., Su M., . Superhydrophobic membranes with ordered arrays of nanospiked microchannels for water desalination. Langmuir. 2009;25(10):5446-5450.
[Google Scholar]

[161] Mahltig B., Böttcher H., . Modified silica sol coatings for water-repellent textiles. J. Sol-Gel Sci. Technol.. 2003;27(1):43-52.
[Google Scholar]

[162] Maitra T., Antonini C., Auf Der Mauer M., Stamatopoulos C., Tiwari M.K., Poulikakos D., . Hierarchically nanotextured surfaces maintaining superhydrophobicity under severely adverse conditions. Nanoscale. 2014;6(15):8710-8719.
[Google Scholar]

[163] Marmur A., . Wetting on hydrophobic rough surfaces: to be heterogeneous or not to be? Langmuir. 2003;19(20):8343-8348.
[Google Scholar]

[164] Martin S., Bhushan B., . Transparent, wear-resistant, superhydrophobic and superoleophobic poly (dimethylsiloxane)(PDMS) surfaces. J. Colloid Interface Sci.. 2017;488:118-126.
[Google Scholar]

[165] McArthur E.A., Ye T., Cross J.P., Petoud S., Borguet E., . Fluorescence detection of surface-bound intermediates produced from UV photoreactivity of alkylsiloxane SAMs. J. Am. Chem. Soc.. 2004;126(8):2260-2261.
[Google Scholar]

[166] McHale G., Flynn M.R., Newton M.I., . Plastron induced drag reduction and increased slip on a superhydrophobic sphere. Soft Matter. 2011;7(21):10100-10107.
[Google Scholar]

[167] Meuler A.J., Smith J.D., Varanasi K.K., Mabry J.M., McKinley G.H., Cohen R.E., . Relationships between water wettability and ice adhesion. ACS Appl. Mater. Interf.. 2010;2(11):3100-3110.
[Google Scholar]

[168] Mo C., Zheng Y., Wang F., Mo Q., . A simple process for fabricating organic/TiO₂ super-hydrophobic and anti-corrosion coating. Int. J. Electrochem. Sci.. 2015;10(9):7380-7391.
[Google Scholar]

[169] Mohamed A.M., Jafari R., Farzaneh M., . An optimization of superhydrophobic polyvinylidene fluoride/zinc oxide materials using Taguchi method. Appl. Surf. Sci.. 2014;288:229-237.
[Google Scholar]

[170] Mohammadi R., Wassink J., Amirfazli A., . Effect of surfactants on wetting of super-hydrophobic surfaces. Langmuir. 2004;20(22):9657-9662.
[Google Scholar]

[171] Momen G., Farzaneh M., . Facile approach in the development of icephobic hierarchically textured coatings as corrosion barrier. Appl. Surf. Sci.. 2014;299:41-46.
[Google Scholar]

[172] Morra M., Occhiello E., Garbassi F., . Contact angle hysteresis in oxygen plasma treated poly (tetrafluoroethylene) Langmuir. 1989;5(3):872-876.
[Google Scholar]

[173] Nakate U.T., Patil P., Bulakhe R., Lokhande C., Kale S.N., Naushad M., Mane R.S., . Sprayed zinc oxide films: Ultra-violet light-induced reversible surface wettability and platinum-sensitization-assisted improved liquefied petroleum gas response. J. Colloid Interf. Sci.. 2016;480:109-117.
[Google Scholar]

[174] Nicolas M., Guittard F., Géribaldi S., . Synthesis of stable super water-and oil-repellent polythiophene films. Angew. Chem. Int. Ed.. 2006;45(14):2251-2254.
[Google Scholar]

[175] Ning T., Xu W., Lu S., . Fabrication of superhydrophobic surfaces on zinc substrates and their application as effective corrosion barriers. Appl. Surf. Sci.. 2011;258(4):1359-1365.
[Google Scholar]

[176] Ogihara H., Okagaki J., Saji T., . Facile fabrication of colored superhydrophobic coatings by spraying a pigment nanoparticle suspension. Langmuir. 2011;27(15):9069-9072.
[Google Scholar]

[177] Oikawa Y., Minami T., Mayama H., Tsujii K., Fushimi K., Aoki Y., Habazaki H., . Preparation of self-organized porous anodic niobium oxide microcones and their surface wettability. Acta Mater.. 2009;57(13):3941-3946.
[CrossRef] [Google Scholar]

[178] Onda T., Shibuichi S., Satoh N., Tsujii K., . Super-water-repellent fractal surfaces. Langmuir. 1996;12(9):2125-2127.
[Google Scholar]

[179] Ou J., Hu W., Wang Y., Wang F., Xue M., Li W., . Construction and corrosion behaviors of a bilayer superhydrophobic film on copper substrate. Surf. Interface Anal.. 2013;45(3):698-704.
[Google Scholar]

[180] Ou J., Hu W., Xue M., Wang F., Li W., . Superhydrophobic surfaces on light alloy substrates fabricated by a versatile process and their corrosion protection. ACS Appl. Mater. Interf.. 2013;5(8):3101-3107.
[Google Scholar]

[181] Ou J., Liu M., Li W., Wang F., Xue M., Li C., . Corrosion behavior of superhydrophobic surfaces of Ti alloys in NaCl solutions. Appl. Surf. Sci.. 2012;258(10):4724-4728.
[Google Scholar]

[182] Pan Q., Wang M., Wang H., . Separating small amount of water and hydrophobic solvents by novel superhydrophobic copper meshes. Appl. Surf. Sci.. 2008;254(18):6002-6006.
[Google Scholar]

[183] Park B., Hwang W., . A facile fabrication method for corrosion-resistant micro/nanostructures on stainless steel surfaces with tunable wettability. Scr. Mater.. 2016;113:118-121.
[Google Scholar]

[184] Parkin I.P., Palgrave R.G., . Self-cleaning coatings. J. Mater. Chem.. 2005;15(17):1689-1695.
[Google Scholar]

[185] Peng M., Li H., Wu L., Zheng Q., Chen Y., Gu W., . Porous poly (vinylidene fluoride) membrane with highly hydrophobic surface. J. Appl. Polym. Sci.. 2005;98(3):1358-1363.
[Google Scholar]

[186] Peng R., Liang L., Hood Z.D., Boulesbaa A., Puretzky A., Ievlev A.V., Wu Z., . In-Plane Heterojunctions Enable Multiphasic Two-Dimensional (2D) MoS2 Nanosheets As Efficient Photocatalysts for Hydrogen Evolution from Water Reduction. ACS Catal.. 2016;6(10):6723-6729.
[CrossRef] [Google Scholar]

[187] Peng S., Tian D., Yang X., Deng W., . Highly efficient and large-scale fabrication of superhydrophobic alumina surface with strong stability based on self-congregated alumina nanowires. ACS Appl. Mater. Interf.. 2005;6(7):4831-4841.
[Google Scholar]

[188] Pilotek S., Schmidt H.K., . Wettability of microstructured hydrophobic sol-gel coatings. J. Sol-Gel Sci. Technol.. 2003;26(1–3):789-792.
[Google Scholar]

[189] Qing G., Sun T., . Chirality-triggered wettability switching on a smart polymer surface. Adv. Mater.. 2011;23(14):1615-1620.
[Google Scholar]

[190] Qing Y., Yang C., Sun Y., Zheng Y., Wang X., Shang Y., Liu C., . Facile fabrication of superhydrophobic surfaces with corrosion resistance by nanocomposite coating of TiO₂ and polydimethylsiloxane. Colloids Surf., A. 2015;484:471-477.
[Google Scholar]

[191] Qing Y., Yang C., Yu N., Shang Y., Sun Y., Wang L., Liu C., . Superhydrophobic TiO₂/polyvinylidene fluoride composite surface with reversible wettability switching and corrosion resistance. Chem. Eng. J.. 2016;290:37-44.
[Google Scholar]

[192] Qu M., Liu S., He J., Feng J., Yao Y., Hou L., Liu X., . Fabrication of recyclable superhydrophobic materials with self-cleaning and mechanically durable properties on various substrates by quartz sand and polyvinylchloride. RSC Adv.. 2016;6(82):79238-79244.
[Google Scholar]

[193] Radwan A.B., Mohamed A.M., Abdullah A.M., Al-Maadeed M.A., . Corrosion protection of electrospun PVDF-ZnO superhydrophobic coating. Surf. Coat. Technol. 2015
[Google Scholar]

[194] Ragesh P., Anand Ganesh V., Nair S.V., Nair A.S., . A review on 'self-cleaning and multifunctional materials' J. Mater. Chem. A. 2014;2(36):14773-14797.
[CrossRef] [Google Scholar]

[195] Rahmawan Y., Xu L., Yang S., . Self-assembly of nanostructures towards transparent, superhydrophobic surfaces. J. Mater. Chem. A. 2013;1(9):2955-2969.
[Google Scholar]

[196] Rao A.V., Latthe S.S., Mahadik S.A., Kappenstein C., . Mechanically stable and corrosion resistant superhydrophobic sol–gel coatings on copper substrate. Appl. Surf. Sci.. 2011;257(13):5772-5776.
[Google Scholar]

[197] Rao A.V., Latthe S.S., Nadargi D.Y., Hirashima H., Ganesan V., . Preparation of MTMS based transparent superhydrophobic silica films by sol–gel method. J. Coll. Interf. Sci.. 2009;332(2):484-490.
[Google Scholar]

[198] Ren L.-F., Xia F., Shao J., Zhang X., Li J., . Experimental investigation of the effect of electrospinning parameters on properties of superhydrophobic PDMS/PMMA membrane and its application in membrane distillation. Desalination. 2017;404:155-166.
[Google Scholar]

[199] Reyssat M., Yeomans J., Quéré D., . Impalement of fakir drops. EPL (Europhys. Lett.). 2007;81(2):26006.
[Google Scholar]

[200] Richard E., Aruna S., Basu B.J., . Superhydrophobic surfaces fabricated by surface modification of alumina particles. Appl. Surf. Sci.. 2012;258(24):10199-10204.
[Google Scholar]

[201] Rothstein J.P., . Slip on superhydrophobic surfaces. Annu. Rev. Fluid Mech.. 2010;42:89-109.
[Google Scholar]

[202] Roy S., Suresh V.M., Maji T.K., . Self-cleaning MOF: Realization of extreme water repellence in coordination driven self-assembled nanostructures. Chem. Sci.. 2016;7(3):2251-2256.
[Google Scholar]

[203] Ryu J., Kim K., Park J., Hwang B.G., Ko Y., Kim H., Lee S.J., . Nearly perfect durable superhydrophobic surfaces fabricated by a simple one-step plasma treatment. Sci. Rep.. 2017;7(1):1981.
[Google Scholar]

[204] Sanchez C., Arribart H., Guille M.M.G., . Biomimetism and bioinspiration as tools for the design of innovative materials and systems. Nat. Mater.. 2005;4(4):277-288.
[Google Scholar]

[205] Seyfoori A., Mirdamadi S., Seyedraoufi Z.S., Khavandi A., Aliofkhazraei M., . Synthesis of biphasic calcium phosphate containing nanostructured films by micro arc oxidation on magnesium alloy. Mater. Chem. Phys.. 2013;142(1):87-94.
[CrossRef] [Google Scholar]

[206] Shang H., Wang Y., Limmer S., Chou T., Takahashi K., Cao G., . Optically transparent superhydrophobic silica-based films. Thin Solid Films. 2005;472(1):37-43.
[Google Scholar]

[207] Sharifi N., Ettouil F.B., Moreau C., Dolatabadi A., Pugh M., . Engineering surface texture and hierarchical morphology of suspension plasma sprayed TiO₂ coatings to control wetting behavior and superhydrophobic properties. Surf. Coat. Technol.. 2017;329:139-148.
[Google Scholar]

[208] She X., Wu J., Xu H., Mo Z., Lian J., Song Y., Li H., . Enhancing charge density and steering charge unidirectional flow in 2D non-metallic semiconductor-CNTs-metal coupled photocatalyst for solar energy conversion. Appl. Catal. B. 2017;202:112-117.
[CrossRef] [Google Scholar]

[209] She Z., Li Q., Wang Z., Li L., Chen F., Zhou J., . Researching the fabrication of anticorrosion superhydrophobic surface on magnesium alloy and its mechanical stability and durability. Chem. Eng. J.. 2017;228:415-424.
[Google Scholar]

[210] She Z., Li Q., Wang Z., Li L., Chen F., Zhou J., . Novel method for controllable fabrication of a superhydrophobic CuO surface on AZ91D magnesium alloy. ACS Appl. Mater. Interf.. 2012;4(8):4348-4356.
[Google Scholar]

[211] She Z., Li Q., Wang Z., Tan C., Zhou J., Li L., . Highly anticorrosion, self-cleaning superhydrophobic Ni-Co surface fabricated on AZ91D magnesium alloy. Surf. Coat. Technol.. 2013;251:7-14.
[Google Scholar]

[212] Sheu H.-H., Lu C.-E., Lee H.-B., Pu N.-W., Wu P.-F., Hsieh S.-H., Ger M.-D., . Electrodeposition of black chromium–cobalt alloy based on trivalent sulfate electrolyte. J. Taiwan Inst. Chem. Eng. 2015
[Google Scholar]

[213] Shi F., Song Y., Niu J., Xia X., Wang Z., Zhang X., . Facile method to fabricate a large-scale superhydrophobic surface by galvanic cell reaction. Chem. Mater.. 2006;18(5):1365-1368.
[Google Scholar]

[214] Shi F., Wang Z., Zhang X., . Combining a layer-by-layer assembling technique with electrochemical deposition of gold aggregates to mimic the legs of water striders. Adv. Mater.. 2005;17(8):1005-1009.
[Google Scholar]

[215] Shi Y., Yang W., Bai J., Feng X., Wang Y., . Fabrication of flower-like copper film with reversible superhydrophobicity–superhydrophilicity and anticorrosion properties. Surf. Coat. Technol.. 2014;253:148-153.
[Google Scholar]

[216] Shibuichi S., Onda T., Satoh N., Tsujii K., . Super water-repellent surfaces resulting from fractal structure. J. Phys. Chem.. 1996;100(50):19512-19517.
[Google Scholar]

[217] Shibuichi S., Yamamoto T., Onda T., Tsujii K., . Super water-and oil-repellent surfaces resulting from fractal structure. J. Colloid Interface Sci.. 1998;208(1):287-294.
[Google Scholar]

[218] Shin S., Seo J., Han H., Kang S., Kim H., Lee T., . Bio-inspired extreme wetting surfaces for biomedical applications. Materials. 2016;9(2)
[CrossRef] [Google Scholar]

[219] Si Y., Guo Z., Liu W., . A robust epoxy resins @ stearic acid-Mg(OH)2 micronanosheet superhydrophobic omnipotent protective coating for real-life applications. ACS Appl. Mater. Interf.. 2016;8(25):16511-16520.
[Google Scholar]

[220] Simpson J.T., Hunter S.R., Aytug T., . Superhydrophobic materials and coatings: a review. Rep. Prog. Phys.. 2015;78(8)
[CrossRef] [Google Scholar]

[221] Skorb E.V., Shchukin D.G., Möhwald H., Andreeva D.V., . Ultrasound-driven design of metal surface nanofoams. Nanoscale. 2010;2(5):722-727.
[Google Scholar]

[222] Soler R., Salabert J., Sebastián R.M., Vallribera A., Roma N., Ricart S., Molins E., . Highly hydrophobic polyfluorinated azo dyes grafted on surfaces. Chem. Commun.. 2011;47(10):2889-2891.
[Google Scholar]

[223] Song T., Liu Q., Zhang M., Chen R., Takahashi K., Jing X., Wang J., . Multiple sheet-layered super slippery surfaces based on anodic aluminium oxide and its anticorrosion property. RSC Adv.. 2015;5(86):70080-70085.
[Google Scholar]

[224] Song Y.Y., Schmidt-Stein F., Berger S., Schmuki P., . TiO₂ nano test tubes as a self-cleaning platform for high-sensitivity immunoassays. Small. 2010;6(11):1180-1184.
[Google Scholar]

[225] Stoiljkovic A., Agarwal S., . Short electrospun fibers by UV cutting method. Macromol. Mater. Eng.. 2008;293(11):895-899.
[Google Scholar]

[226] Su B., Tian Y., Jiang L., . Bioinspired interfaces with superwettability: from materials to chemistry. J. Am. Chem. Soc.. 2016;138(6):1727-1748.
[CrossRef] [Google Scholar]

[227] Su F., Yao K., . Facile fabrication of superhydrophobic surface with excellent mechanical abrasion and corrosion resistance on copper substrate by a novel method. ACS Appl. Mater. Interf.. 2014;6(11):8762-8770.
[Google Scholar]

[228] Su F., Yao K., Liu C., Huang P., . Rapid fabrication of corrosion resistant and superhydrophobic cobalt coating by a one-step electrodeposition. J. Electrochem. Soc.. 2013;160(11):D593-D599.
[Google Scholar]

[229] Sun Q., Liu H., Chen T., Wei Y., Wei Z., . Facile fabrication of iron-based superhydrophobic surfaces via electric corrosion without bath. Appl. Surf. Sci.. 2016;369:277-287.
[Google Scholar]

[230] Tadanaga K., Kitamuro K., Matsuda A., Minami T., . Formation of superhydrophobic alumina coating films with high transparency on polymer substrates by the sol-gel method. J. Sol-Gel Sci. Technol.. 2003;26(1):705-708.
[Google Scholar]

[231] Tadanaga K., Morinaga J., Minami T., . Formation of superhydrophobic-superhydrophilic pattern on flowerlike alumina thin film by the sol-gel method. J. Sol-Gel Sci. Technol.. 2000;19(1–3):211-214.
[Google Scholar]

[232] Tam J., Palumbo G., Erb U., . Recent advances in superhydrophobic electrodeposits. Materials. 2016;9(3):151.
[Google Scholar]

[233] Tan C., Li Q., Cai P., Yang N., Xi Z., . Fabrication of color-controllable superhydrophobic copper compound coating with decoration performance. Appl. Surf. Sci.. 2015;328:623-631.
[Google Scholar]

[234] Tang M.-K., Huang X.-J., Li X.-W., Huang Z.-Y., Zhang S.-M., Zhang Q.-X., . Fabrication of superhydrophobic surface with superior anticorrosion and great mechanical stability on AA7075 Al alloy via a convenient and efficient approach. Mater. Exp.. 2016;6(2):101-115.
[Google Scholar]

[235] Tang M.-K., Zhang Q.-X., Guo Z., Yu J.-G., Li X.-W., Huang X.-J., . A universal laser marking approach for treating aluminum alloy surfaces with enhanced anticorrosion, hardness and reduced friction. RSC Adv.. 2015;5(23):18057-18066.
[Google Scholar]

[236] Tang M.K., Huang X.J., Guo Z., Yu J.G., Li X.W., Zhang Q.X., . Fabrication of robust and stable superhydrophobic surface by a convenient, low-cost and efficient laser marking approach. Coll. Surf. A: Physicochem. Eng. Aspects. 2016;484:449-456.
[Google Scholar]

[237] Tarwal N., Rajgure A., Inamdar A., Devan R., Kim I., Suryavanshi S., Patil P., . Growth of multifunctional ZnO thin films by spray pyrolysis technique. Sens. Actuators, A. 2013;199:67-73.
[Google Scholar]

[238] Thanawala S.K., Chaudhury M.K., . Surface modification of silicone elastomer using perfluorinated ether. Langmuir. 2000;16(3):1256-1260.
[Google Scholar]

[239] Tian D., Zhang X., Tian Y., Wu Y., Wang X., Zhai J., Jiang L., . Photo-induced water–oil separation based on switchable superhydrophobicity–superhydrophilicity and underwater superoleophobicity of the aligned ZnO nanorod array-coated mesh films. J. Mater. Chem.. 2012;22(37):19652-19657.
[Google Scholar]

[240] Tourkine P., Le Merrer M., Quéré D., . Delayed freezing on water repellent materials. Langmuir. 2009;25(13):7214-7216.
[Google Scholar]

[241] Truesdell R., Mammoli A., Vorobieff P., van Swol F., Brinker C.J., . Drag reduction on a patterned superhydrophobic surface. Phys. Rev. Lett.. 2006;97(4):044504.
[Google Scholar]

[242] Tsujii K., Yamamoto T., Onda T., Shibuichi S., . Super oil-repellent surfaces. Angew. Chem., Int. Ed. Engl.. 1997;36(9):1011-1012.
[Google Scholar]

[243] Tuteja A., Choi W., Ma M., Mabry J.M., Mazzella S.A., Rutledge G.C., Cohen R.E., . Designing superoleophobic surfaces. Science. 2007;318(5856):1618-1622.
[Google Scholar]

[244] Victor J., Facchini D., Erb U., . A low-cost method to produce superhydrophobic polymer surfaces. J. Mater. Sci.. 2012;47(8):3690-3697.
[Google Scholar]

[245] Vrancken R.J., Kusumaatmaja H., Hermans K., Prenen A.M., Pierre-Louis O., Bastiaansen C.W., Broer D.J., . Fully reversible transition from Wenzel to Cassie− Baxter states on corrugated superhydrophobic surfaces. Langmuir. 2009;26(5):3335-3341.
[Google Scholar]

[246] Wang C.-H., Song Y.-Y., Zhao J.-W., Xia X.-H., . Semiconductor supported biomimetic superhydrophobic gold surfaces by the galvanic exchange reaction. Surf. Sci.. 2006;600(4):38-42.
[Google Scholar]

[247] Wang C., Yao T., Wu J., Ma C., Fan Z., Wang Z., Yang B., . Facile approach in fabricating superhydrophobic and superoleophilic surface for water and oil mixture separation. ACS Appl. Mater. Interf.. 2009;1(11):2613-2617.
[Google Scholar]

[248] Wang G., Liu S., Wei S., Liu Y., Lian J., Jiang Q., . Robust superhydrophobic surface on Al substrate with durability, corrosion resistance and ice-phobicity. Scient. Rep.. 2016;6
[Google Scholar]

[249] Wang H., Liu Z., Wang E., Yuan R., Gao D., Zhang X., Zhu Y., . A robust superhydrophobic PVDF composite coating with wear/corrosion-resistance properties. Appl. Surf. Sci.. 2015;332:518-524.
[Google Scholar]

[250] Wang J., Li D., Liu Q., Yin X., Zhang Y., Jing X., Zhang M., . Fabrication of hydrophobic surface with hierarchical structure on Mg alloy and its corrosion resistance. Electrochim. Acta. 2010;55(22):6897-6906.
[Google Scholar]

[251] Wang N., Zhao Y., Jiang L., . Low-cost, thermoresponsive wettability of surfaces: poly (N-isopropylacrylamide)/polystyrene composite films prepared by electrospinning. Macromol. Rapid Commun.. 2008;29(6):485-489.
[Google Scholar]

[252] Wang P., Qiu R., Zhang D., Lin Z., Hou B., . Fabricated super-hydrophobic film with potentiostatic electrolysis method on copper for corrosion protection. Electrochim. Acta. 2010;56(1):517-522.
[Google Scholar]

[253] Wang P., Zhang D., Qiu R., . Liquid/solid contact mode of super-hydrophobic film in aqueous solution and its effect on corrosion resistance. Corros. Sci.. 2012;54:77-84.
[Google Scholar]

[254] Wang P., Zhang D., Qiu R., Hou B., . Super-hydrophobic film prepared on zinc as corrosion barrier. Corros. Sci.. 2011;53(6):2080-2086.
[Google Scholar]

[255] Wang P., Zhang D., Qiu R., Wu J., Wan Y., . Super-hydrophobic film prepared on zinc and its effect on corrosion in simulated marine atmosphere. Corros. Sci.. 2013;69:23-30.
[Google Scholar]

[256] Wang S., Feng L., Jiang L., . One-Step Solution-Immersion Process for the Fabrication of Stable Bionic Superhydrophobic Surfaces. Adv. Mater.. 2006;18(6):767-770.
[Google Scholar]

[257] Wang S., Guo X., Xie Y., Liu L., Yang H., Zhu R., Ding W., . Preparation of superhydrophobic silica film on Mg–Nd–Zn–Zr magnesium alloy with enhanced corrosion resistance by combining micro-arc oxidation and sol–gel method. Surf. Coat. Technol.. 2012;213:192-201.
[Google Scholar]

[258] Wang S., Song Y., Jiang L., . Microscale and nanoscale hierarchical structured mesh films with superhydrophobic and superoleophilic properties induced by long-chain fatty acids. Nanotechnology. 2006;18(1):015103.
[Google Scholar]

[259] Wang W.-K., Zheng M.-L., Chen W.-Q., Jin F., Cao Y.-Y., Zhao Z.-S., Duan X.-M., . Microscale golden candock leaves self-aggregated on a polymer surface: Raman scattering enhancement and superhydrophobicity. Langmuir. 2011;27(7):3249-3253.
[Google Scholar]

[260] Wang X., Shen Y., Xie A., Qiu L., Li S., Wang Y., . Novel structure CuI/PANI nanocomposites with bifunctions: superhydrophobicity and photocatalytic activity. J. Mater. Chem.. 2011;21(26):9641-9646.
[Google Scholar]

[261] Wang X., Zheng Y., Yuan J., Shen J., Hu J., Wang A.J., Niu L., . Porous NiCo diselenide nanosheets arrayed on carbon cloth as promising advanced catalysts used in water splitting. Electrochim. Acta. 2017;225:503-513.
[CrossRef] [Google Scholar]

[262] Wang Y., Chen L., Yu X., Wang Y., Zheng G., . Superb alkaline hydrogen evolution and simultaneous electricity generation by Pt-decorated Ni3N nanosheets. Adv. Energy Mater.. 2017;7(2)
[CrossRef] [Google Scholar]

[263] Wang Y., Wang W., Zhong L., Wang J., Jiang Q., Guo X., . Super-hydrophobic surface on pure magnesium substrate by wet chemical method. Appl. Surf. Sci.. 2010;256(12):3837-3840.
[Google Scholar]

[264] Wen Q., Di J., Jiang L., Yu J., Xu R., . Zeolite-coated mesh film for efficient oil–water separation. Chem. Sci.. 2013;4(2):591-595.
[Google Scholar]

[265] Wen X.-F., Wang K., Pi P.-H., Yang J.-X., Cai Z.-Q., Zhang L.-J., Cheng J., . Organic–inorganic hybrid superhydrophobic surfaces using methyltriethoxysilane and tetraethoxysilane sol–gel derived materials in emulsion. Appl. Surf. Sci.. 2011;258(3):991-998.
[Google Scholar]

[266] Wenzel R.N., . Resistance of solid surfaces to wetting by water. Ind. Eng. Chem.. 1936;28(8):988-994.
[Google Scholar]

[267] Williams S.J., Davies G.J., . Protein–carbohydrate interactions: learning lessons from nature. Trends Biotechnol.. 2001;19(9):356-362.
[Google Scholar]

[268] Woodward I., Schofield W., Roucoules V., Badyal J., . Super-hydrophobic surfaces produced by plasma fluorination of polybutadiene films. Langmuir. 2003;19(8):3432-3438.
[Google Scholar]

[269] Woodward J., Gwin H., Schwartz D., . Contact angles on surfaces with mesoscopic chemical heterogeneity. Langmuir. 2000;16(6):2957-2961.
[Google Scholar]

[270] Wu F., Liang J., Peng Z., Liu B., . Electrochemical deposition and characterization of Zn-Al layered double hydroxides (LDHs) films on magnesium alloy. Appl. Surf. Sci.. 2014;313:834-840.
[Google Scholar]

[271] Wu L.-K., Zhang X.-F., Hu J.-M., . Corrosion protection of mild steel by one-step electrodeposition of superhydrophobic silica film. Corros. Sci.. 2014;85:482-487.
[Google Scholar]

[272] Wu L., Zhang J., Li B., Wang A., . Mechanical- and oil-durable superhydrophobic polyester materials for selective oil absorption and oil/water separation. J. Colloid Interf. Sci.. 2014;413:112-117.
[Google Scholar]

[273] Wu L.K., Hu J.M., Zhang J.Q., . One step sol-gel electrochemistry for the fabrication of superhydrophobic surfaces. J. Mater. Chem. A. 2014;1(46):14471-14475.
[Google Scholar]

[274] Wu W., Wang X., Liu X., Zhou F., . Spray-coated fluorine-free superhydrophobic coatings with easy repairability and applicability. ACS Appl. Mater. Interf.. 2009;1(8):1656-1661.
[Google Scholar]

[275] Wu X., Zheng L., Wu D., . Fabrication of superhydrophobic surfaces from microstructured ZnO-based surfaces via a wet-chemical route. Langmuir. 2005;21(7):2665-2667.
[Google Scholar]

[276] Wu Y., Zhao W., Wang W., Sui W., . Fabricating binary anti-corrosion structures containing superhydrophobic surfaces and sturdy barrier layers for Al alloys. RSC Adv.. 2016;6(6):5100-5110.
[Google Scholar]

[277] Xiao J., Lv Q., Zhang Y., Zhang Z., Wang S., . One-step synthesis of nickel phosphide nanowire array supported on nickel foam with enhanced electrocatalytic water splitting performance. RSC Adv.. 2016;6(109):107859-107864.
[CrossRef] [Google Scholar]

[278] Xiu Y., Liu Y., Hess D.W., Wong C., . Mechanically robust superhydrophobicity on hierarchically structured Si surfaces. Nanotechnology. 2010;21(15):155705.
[Google Scholar]

[279] Xu F., Zhang Y., Sun Y., Shi Y., Wen Z., Li Z., . Silver nanoparticles coated zinc oxide nanorods array as superhydrophobic substrate for the amplified SERS effect. J. Phys. Chem. C. 2011;115(20):9977-9983.
[Google Scholar]

[280] Xu N., Sarkar D., Chen X.-G., Tong W., . Corrosion performance of superhydrophobic nickel stearate/nickel hydroxide thin films on aluminum alloy by a simple one-step electrodeposition process. Surf. Coat. Technol.. 2016;302:173-184.
[Google Scholar]

[281] Xu Q., Zhao Q., Zhu X., Cheng L., Bai S., Wang Z., Qin Y., . A new kind of transparent and self-cleaning film for solar cells. Nanoscale. 2016;8(41):17747-17751.
[Google Scholar]

[282] Xu W., Shi X., Lu S., . Controlled growth of superhydrophobic films without any low-surface-energy modification by chemical displacement on zinc substrates. Mater. Chem. Phys.. 2011;129(3):1042-1046.
[Google Scholar]

[283] Xu W., Song J., Sun J., Lu Y., Yu Z., . Rapid fabrication of large-area, corrosion-resistant superhydrophobic Mg alloy surfaces. ACS Appl. Mater. Interf.. 2011;3(11):4404-4414.
[Google Scholar]

[284] Xu X., Zhang Z., Guo F., Yang J., Zhu X., Zhou X., Xue Q., . Superamphiphobic self-assembled monolayer of thiol on the structured Zn surface. Coll. Surf. A: Physicochem. Eng. Aspects. 2012;396:90-95.
[Google Scholar]

[285] Xu X., Zhang Z., Yang J., . Fabrication of biomimetic superhydrophobic surface on engineering materials by a simple electroless galvanic deposition method. Langmuir. 2009;26(5):3654-3658.
[Google Scholar]

[286] Xu X.H., Zhang Z.Z., Yang J., Zhu X., . Study of the corrosion resistance and loading capacity of superhydrophobic meshes fabricated by spraying method. Colloids Surf., A. 2011;377(1):70-75.
[Google Scholar]

[287] Xue L., Li J., Fu J., Han Y., . Super-hydrophobicity of silica nanoparticles modified with vinyl groups. Colloids Surf., A. 2009;338(1):15-19.
[Google Scholar]

[288] Yan H., Kurogi K., Mayama H., Tsujii K., . Environmentally stable super water-repellent poly (alkylpyrrole) films. Angew. Chem. Int. Ed.. 2005;44(22):3453-3456.
[Google Scholar]

[289] Yang H., Pi P., Cai Z.-Q., Wen X., Wang X., Cheng J., Yang Z.-R., . Facile preparation of super-hydrophobic and super-oleophilic silica film on stainless steel mesh via sol–gel process. Appl. Surf. Sci.. 2010;256(13):4095-4102.
[Google Scholar]

[290] Yang N., Li J., Bai N., Xu L., Li Q., . One step phase separation process to fabricate superhydrophobic PVC films and its corrosion prevention for AZ91D magnesium alloy. Mater. Sci. Eng., B. 2016;209:1-9.
[Google Scholar]

[291] Yang N., Li Q., Chen F., Cai P., Tan C., Xi Z., . A solving-reprecipitation theory for self-healing functionality of stannate coating with a high environmental stability. Electrochim. Acta. 2015;174:1192-1201.
[Google Scholar]

[292] Yang Q., He Y., Fan Y., Li F., Chen X., . Exfoliation of the defect-rich MoS2 nanosheets to obtain nanodots modified MoS2 thin nanosheets for electrocatalytic hydrogen evolution. J. Mater. Sci.: Mater. Electron.. 2017;1–6
[CrossRef] [Google Scholar]

[293] Yao L., He J., . Recent progress in antireflection and self-cleaning technology–From surface engineering to functional surfaces. Prog. Mater Sci.. 2014;61:94-143.
[Google Scholar]

[294] Ye J., Yin Q., Zhou Y., . Superhydrophilicity of anodic aluminum oxide films: From “honeycomb” to “bird's nest”. Thin Solid Films. 2009;517(21):6012-6015.
[Google Scholar]

[295] Yin B., Fang L., Hu J., Tang A., He J., Mao J., . A facile method for fabrication of superhydrophobic coating on aluminum alloy. Surf. Interface Anal.. 2012;44(4):439-444.
[Google Scholar]

[296] Yin B., Fang L., Tang A.-Q., Huang Q.-L., Hu J., Mao J.-H., Bai H., . Novel strategy in increasing stability and corrosion resistance for super-hydrophobic coating on aluminum alloy surfaces. Appl. Surf. Sci.. 2011;258(1):580-585.
[Google Scholar]

[297] Yin L., Wang Y., Ding J., Wang Q., Chen Q., . Water condensation on superhydrophobic aluminum surfaces with different low-surface-energy coatings. Appl. Surf. Sci.. 2012;258(8):4063-4068.
[Google Scholar]

[298] Yohe S.T., Colson Y.L., Grinstaff M.W., . Superhydrophobic materials for tunable drug release: using displacement of air to control delivery rates. J. Am. Chem. Soc.. 2012;134(4):2016-2019.
[Google Scholar]

[299] You J.-H., Lee B.-I., Lee J., Kim H., Byeon S.-H., . Superhydrophilic and antireflective La (OH) 3/SiO 2-nanorod/nanosphere films. J. Coll. Interf. Sci.. 2011;354(1):373-379.
[Google Scholar]

[300] Young T., . An essay on the cohesion of fluids. Philos. Trans. R. Soc. Lond.. 1805;95:65-87.
[Google Scholar]

[301] Youngblood J.P., McCarthy T.J., . Ultrahydrophobic polymer surfaces prepared by simultaneous ablation of polypropylene and sputtering of poly (tetrafluoroethylene) using radio frequency plasma. Macromolecules. 1999;32(20):6800-6806.
[Google Scholar]

[302] Yu M., Gu G., Meng W.-D., Qing F.-L., . Superhydrophobic cotton fabric coating based on a complex layer of silica nanoparticles and perfluorooctylated quaternary ammonium silane coupling agent. Appl. Surf. Sci.. 2007;253(7):3669-3673.
[Google Scholar]

[303] Yu X., Wang Z., Jiang Y., Shi F., Zhang X., . Reversible pH-responsive surface: from superhydrophobicity to superhydrophilicity. Adv. Mater.. 2005;17(10):1289-1293.
[Google Scholar]

[304] Yu X., Wang Z., Jiang Y., Zhang X., . Surface gradient material: from superhydrophobicity to superhydrophilicity. Langmuir. 2006;22(10):4483-4486.
[Google Scholar]

[305] Yuan S., Pehkonen S., Liang B., Ting Y., Neoh K., Kang E., . Superhydrophobic fluoropolymer-modified copper surface via surface graft polymerisation for corrosion protection. Corr. Sci.. 2011;53(9):2738-2747.
[Google Scholar]

[306] Yuan Y., Lee T.R., . Contact Angle and Wetting Properties Surface Science Techniques. Springer; 2013. (pp. 3–34)

[307] Yue W.-W., Li H.-J., Xiang T., Qin H., Sun S.-D., Zhao C.-S., . Grafting of zwitterion from polysulfone membrane via surface-initiated ATRP with enhanced antifouling property and biocompatibility. J. Membr. Sci.. 2013;446:79-91.
[Google Scholar]

[308] Yung C.S., Tomlin N.A., Heuerman K., Keller M.W., White M.G., Stephens M., Lehman J.H., . Plasma modification of vertically aligned carbon nanotubes: Superhydrophobic surfaces with ultra-low reflectance. Carbon. 2018;127:195-201.
[Google Scholar]

[309] Zeng C., Wang H., Zhou H., Lin T., . Self-cleaning, superhydrophobic cotton fabrics with excellent washing durability, solvent resistance and chemical stability prepared from an SU-8 derived surface coating. RSC Adv.. 2015;5(75):61044-61050.
[Google Scholar]

[310] Zhai L., Berg M.C., Cebeci F.C., Kim Y., Milwid J.M., Rubner M.F., Cohen R.E., . Patterned superhydrophobic surfaces: toward a synthetic mimic of the Namib Desert beetle. Nano Lett.. 2006;6(6):1213-1217.
[Google Scholar]

[311] Zhang B., Feng H., Lin F., Wang Y., Wang L., Dong Y., Li W., . Superhydrophobic surface fabricated on iron substrate by black chromium electrodeposition and its corrosion resistance property. Appl. Surf. Sci.. 2016;378:388-396.
[Google Scholar]

[312] Zhang B., Li Y., Hou B., . One-step electrodeposition fabrication of a superhydrophobic surface on an aluminum substrate with enhanced self-cleaning and anticorrosion properties. RSC Adv.. 2015;5(121):100000-100010.
[Google Scholar]

[313] Zhang B., Lu S., Xu W., Cheng Y., . Controllable wettability and morphology of electrodeposited surfaces on zinc substrates. Appl. Surf. Sci.. 2016;360:904-914.
[Google Scholar]

[314] Zhang B., Zhao X., Li Y., Hou B., . Fabrication of durable anticorrosion superhydrophobic surfaces on aluminum substrates via a facile one-step electrodeposition approach. RSC Adv.. 2016;6(42):35455-35465.
[Google Scholar]

[315] Zhang D.-Q., Cai Q.-R., He X.-M., Gao L.-X., Kim G.S., . The corrosion inhibition of copper in hydrochloric acid solutions by a tripeptide compound. Corros. Sci.. 2009;51(10):2349-2354.
[Google Scholar]

[316] Zhang F., Chen S., Dong L., Lei Y., Liu T., Yin Y., . Preparation of superhydrophobic films on titanium as effective corrosion barriers. Appl. Surf. Sci.. 2011;257(7):2587-2591.
[Google Scholar]

[317] Zhang F., Zhang C., Song L., Zeng R., Li S., Cui H., . Fabrication of the superhydrophobic surface on magnesium alloy and its corrosion resistance. J. Mater. Sci. Technol.. 2015;31(11):1139-1143.
[Google Scholar]

[318] Zhang F., Zhang C., Zeng R., Song L., Guo L., Huang X., . Corrosion resistance of the superhydrophobic Mg (OH) 2/Mg-Al layered double hydroxide coatings on magnesium alloys. Metals. 2016;6(4):85.
[Google Scholar]

[319] Zhang F., Zhao L., Chen H., Xu S., Evans D.G., Duan X., . Corrosion resistance of superhydrophobic layered double hydroxide films on aluminum. Angew. Chem. Int. Ed.. 2008;47(13):2466-2469.
[Google Scholar]

[320] Zhang H., Yang J., Chen B., Liu C., Zhang M., Li C., . Fabrication of superhydrophobic textured steel surface for anti-corrosion and tribological properties. Appl. Surf. Sci.. 2015;359:905-910.
[Google Scholar]

[321] Zhang H., Yin L., Shi S., Liu X., Wang Y., Wang F., . Facile and fast fabrication method for mechanically robust superhydrophobic surface on aluminum foil. Microelectron. Eng.. 2015;141:238-242.
[Google Scholar]

[322] Zhang J.J., Sui X.L., Huang G.S., Gu D.M., Wang Z.B., . Hierarchical carbon coated molybdenum dioxide nanotubes as a highly active and durable electrocatalytic support for methanol oxidation. J. Mater. Chem. A. 2017;5(8):4067-4074.
[CrossRef] [Google Scholar]

[323] Zhang Q., Wang Y., Wang Y., Al-Enizi A.M., Elzatahry A.A., Zheng G., . Myriophyllum -like hierarchical TiN@Ni3N nanowire arrays for bifunctional water splitting catalysts. J. Mater. Chem. A. 2016;4(15):5713-5718.
[CrossRef] [Google Scholar]

[324] Zhang Q., Xia F., Sun T., Song W., Zhao T., Liu M., Jiang L., . Wettability switching between high hydrophilicity at low pH and high hydrophobicity at high pH on surface based on pH-responsive polymer. Chem. Commun.. 2008;10:1199-1201.
[Google Scholar]

[325] Zhang W., Wang S., Yu X., Zhang Y., . Fabrication of non-modified metallic superhydrophobic surfaces with temperature insensitivity and self-healing ability. Appl. Phys. Lett.. 2016;109(4)
[CrossRef] [Google Scholar]

[326] Zhang X., Shi F., Niu J., Jiang Y., Wang Z., . Superhydrophobic surfaces: from structural control to functional application. J. Mater. Chem.. 2008;18(6):621-633.
[Google Scholar]

[327] Zhang Y., Chen X., Huang Y., Zhang C., Li F., Shu H., . The role of intrinsic defects in electrocatalytic activity of monolayer VS2 basal planes for the hydrogen evolution reaction. J. Phys. Chem. C. 2017;121(3):1530-1536.
[CrossRef] [Google Scholar]

[328] Zhang Z., Ge B., Men X., Li Y., . Mechanically durable, superhydrophobic coatings prepared by dual-layer method for anti-corrosion and self-cleaning. Colloids Surf., A. 2016;490:182-188.
[Google Scholar]

[329] Zhao K., Liu K., Li J., Wang W., Jiang L., . Superamphiphobic CaLi-based bulk metallic glasses. Scripta materialia. 2009;60(4):225-227.
[Google Scholar]

[330] Zhao L., Hong C., Lin L., Wu H., Su Y., Zhang X., Liu A., . Controllable nanoscale engineering of vertically aligned MoS2 ultrathin nanosheets by nitrogen doping of 3D graphene hydrogel for improved electrocatalytic hydrogen evolution. Carbon. 2017;116:223-231.
[CrossRef] [Google Scholar]

[331] Zhao L., Liu Q., Gao R., Wang J., Yang W., Liu L., . One-step method for the fabrication of superhydrophobic surface on magnesium alloy and its corrosion protection, antifouling performance. Corros. Sci.. 2014;80:177-183.
[CrossRef] [Google Scholar]

[332] Zhao N., Shi F., Wang Z., Zhang X., . Combining layer-by-layer assembly with electrodeposition of silver aggregates for fabricating superhydrophobic surfaces. Langmuir. 2005;21(10):4713-4716.
[Google Scholar]

[333] Zhao N., Xie Q., Weng L., Wang S., Zhang X., Xu J., . Superhydrophobic surface from vapor-induced phase separation of copolymer micellar solution. Macromolecules. 2005;38(22):8996-8999.
[Google Scholar]

[334] Zhao Y., Xu Z., Wang X., Lin T., . Photoreactive azido-containing silica nanoparticle/polycation multilayers: durable superhydrophobic coating on cotton fabrics. Langmuir. 2012;28(15):6328-6335.
[Google Scholar]

[335] Zheludkevich M., Poznyak S., Rodrigues L., Raps D., Hack T., Dick L., Ferreira M., . Active protection coatings with layered double hydroxide nanocontainers of corrosion inhibitor. Corros. Sci.. 2010;52(2):602-611.
[Google Scholar]

[336] Zheng S., Li C., Fu Q., Hu W., Xiang T., Wang Q., Chen Z., . Development of stable superhydrophobic coatings on aluminum surface for corrosion-resistant, self-cleaning, and anti-icing applications. Mater. Des.. 2016;93:261-270.
[Google Scholar]

[337] Zheng S., Li C., Fu Q., Li M., Hu W., Wang Q., Chen Z., . Fabrication of self-cleaning superhydrophobic surface on aluminum alloys with excellent corrosion resistance. Surf. Coat. Technol.. 2015;276:341-348.
[Google Scholar]

[338] Zhou M., Pang X., Wei L., Gao K., . Insitu grown superhydrophobic Zn–Al layered double hydroxides films on magnesium alloy to improve corrosion properties. Appl. Surf. Sci.. 2015;337:172-177.
[Google Scholar]

[339] Zhou Y., Xiao H., Wang S., Pan X., Wang Z., An C., Zhang J., . Synthesis of layer-expanded MoS2 nanosheets/carbon fibers nanocomposites for electrochemical hydrogen evolution reaction. Mater. Chem. Phys.. 2016;183:18-23.
[CrossRef] [Google Scholar]

[340] Zhu H., Chen D., Li N., Xu Q., Li H., He J., Lu J., . Dual-layer copper mesh for integrated oil-Water separation and water purification. Appl. Catal. B. 2017;200:594-600.
[Google Scholar]

[341] Zhu X., Zhang Z., Men X., Yang J., Wang K., Xu X., Xue Q., . Robust superhydrophobic surfaces with mechanical durability and easy repairability. J. Mater. Chem.. 2011;21(39):15793-15797.
[Google Scholar]

[342] Zhu X., Zhang Z., Ren G., Men X., Ge B., Zhou X., . Designing transparent superamphiphobic coatings directed by carbon nanotubes. J. Colloid Interf. Sci.. 2014;421:141-145.
[Google Scholar]

[343] Zhu X., Zhang Z., Yang J., Xu X., Men X., Zhou X., . Facile fabrication of a superhydrophobic fabric with mechanical stability and easy-repairability. J. Colloid Interf. Sci.. 2012;380(1):182-186.
[Google Scholar]

[344] Zimmermann J., Reifler F.A., Fortunato G., Gerhardt L.C., Seeger S., . A simple, one-step approach to durable and robust superhydrophobic textiles. Adv. Funct. Mater.. 2008;18(22):3662-3669.
[Google Scholar]

[345] Zou, L., Lan, C., Li, X., Zhang, S., Qiu, Y., Ma, Y. Superhydrophobization of cotton fabric with multiwalled carbon nanotubes for durable electromagnetic interference shielding. Fibers Polym. 16(10), 2158–2164.

[346] Zou W., Zhang L., Liu L., Wang X., Sun J., Wu S., Dong L., . Engineering the Cu₂O–reduced graphene oxide interface to enhance photocatalytic degradation of organic pollutants under visible light. Appl. Catal. B. 2016;181:495-503.
[Google Scholar]

Science and Engineering of Superhydrophobic Surfaces: Review of Corrosion Resistance, Chemical and Mechanical Stability

Abstract

Keywords

Chemical durability

Corrosion resistance

Mechanical stability

Superhydrophobic surfaces

1 Introduction

2 Wetting phenomena

2.1 Wettability

2.2 Requirements for fabrication of SHS

2.2.1 Surface energy

2.2.2 Surface roughness

2.3 Wetting models

2.4 Rolling angle and the wetting angle hysteresis

3 Application of superhydrophobic surfaces

3.1 Increase of corrosion resistance

3.2 Anti-fogging surfaces

3.3 Anti-bacterial surfaces

3.4 Anti-icing surfaces

3.5 Oil and water separation

3.6 Self-cleaning surfaces

3.7 Drag reduction

3.8 Battery manufacture technology

3.9 Sensors

3.10 Water purification

3.11 Optical devices

3.12 Membrane distillation and water desalination

3.13 Microfluidic devices

3.14 Other applications

4 Fabrication of SHS

4.1 Sol-gel method

4.2 Electrospinning

4.3 Electrochemical methods

4.4 Layer-by-layer method

4.5 Plasma techniques

4.6 Other important methods

5 Corrosion resistance of SHS

5.1 Electrodeposition method

5.2 Chemical fabrication methods

5.3 Sol-gel fabrication method

5.4 Spray coating fabrication method

5.5 Hydrothermal synthesis fabrication method

5.6 Electrospinning fabrication method

5.7 Laser operations fabrication method

5.8 Methods based on anodic oxidation

5.8.1 PEO and MAO

5.8.2 Anodizing method

5.9 Plasma techniques

5.10 Other fabrication methods

6 Chemical stability

6.1 The necessity of chemical stability investigation

6.2 Chemical stability fading mechanisms

6.2.1 Loss of roughness

6.2.2 Dissolution of surface layer

6.3 Chemical stability evaluation

6.3.1 Contact angle versus pH variations

6.3.2 Contact angle versus immersion time

6.3.3 Acid rain test

6.3.4 Droplet test in vapor-saturated atmosphere

6.4 Chemical stability improvement approaches

7 Mechanical stability

7.1 Necessity of mechanical stability

7.2 Fading mechanism of superhydrophobicity due to mechanical contacts

7.3 Important approaches for improvement of mechanical stability

8 Concluding remarks and future trends

References

Suggested read for related articles: