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In this work, a translucent superhydrophobic coating was fabricated by a simple spray-coating technique using fluorine-free and easily available materials, viz , the hybrids of PDMS and PMMA in THF solution, without any pre-/post-treatment. The combination of the microscale roughness of the sprayed-PMMA, along with the low surface energy PDMS, has contributed to the observed superhydrophobicity. The as-prepared PDMS/PMMA@superhydrophobic surface has displayed a water contact angle of 157.5° and sliding angle of 2.8°. Furthermore, the liquids with various surface tension, ranging from water to various organic liquids, displayed nearly spherical shapes on the superhydrophobic substrate. In addition, this coating has also shown significant stability against sand abrasion and water droplet impact, and was able to maintain its superhydrophobicity after being soaked in strong acid and salkali solutions. Moreover, the superhydrophobic coating was found to be translucent with good visibility of the characters through the coated glass substrate. The transformation from a superhydrophobic state to superhydrophilic state can be realized via a hot-press process, and such a facile technique can be easily applied to potential applications in surface patterning. Additionally, the super-antiwetting surface has been demonstrated for applications in highly efficient oil-water emulsion separation, anti-fouling, and self-cleaning. [ABSTRACT FROM AUTHOR]

The superhydrophobic TiO 2 coating was fabricated on cotton fabric through a facile one step hot-pressing process after being dipped in n-octyltriethoxysilane and Ti-containing precursor mixed solution. The as-prepared fabric exhibited robust superhydrophobic with a water contact angle higher than 150° and realized an optimized UV protective factor of 45. The as-constructed superhydrophobic fabric was able to withstand more than 800 cycles of abrasion. Moreover, there was not apparent decrease of superhydrophobicity after 10 cycles of accelerated machine wash and the as-constructed fabric also showed a strong ability to resist acidic and alkaline solutions. Finally, the potential applications of such value-added fabrics self-cleaning, anti-fouling, and water-oil separation were investigated as well. The results demonstrated that the combination of n-octyltriethoxysilane and Ti-containing precursor coating endowed the pristine fabrics with excellent self-cleaning for dusts and anti-fouling for methylene blue dye, as well as excellent separation efficiency for the oil-water mixtures. This facile synthesis stragegy can also be extended to quickly construct multifunctional fabrics with speical wettability in a large scale and utilized in some promising fields. [ABSTRACT FROM AUTHOR]

Despite the existing effort, fabricating superhydrophobic substrate through an environmental friendly approach remains a great challenge. In the current work, we present a simple approach to fabricate robust superhydrophobic surfaces on different kinds of substrates using phase-separation method. This method uses polydimethylsiloxane (PDMS) as the binder, tetrahydrofuran (THF) as the solvent, and water as nonsolvent. The emulsion prepared under optimum proportion of THF and water was stable and showed no obvious change even after being stored for 6 weeks. The coated substrates exhibit superhydrophobic property with a water contact angle (CA) larger than 155.0°. Moreover, because the solution is rich of water, and the surface modification condition is mild, the PDMS coating enjoys a high degree of transparency. Finally, superhydrophobic cotton and sponge were successfully demonstrated for oil-water and oil-in-water emulsion separation. This facile synthesis method has a potential for a broad range of applications in large-scale fabrication of superhydrophobic surfaces and filtration membranes. [ABSTRACT FROM AUTHOR]

It remains a great challenge to prepare multi-functional fabrics using a low-cost and scalable method with fluorine-free materials. In this paper, we report a new procedure for producing fluorine-free super hydrophobic cotton fabrics, via a simple dip-coating process. Firstly, a polydimethylsiloxane (PDMS) adhesive layer is deposited onto the cotton substrate, followed by the subsequent deposition of ZnO nanoparticles to enhance the surface roughness through an oil bath process. Finally, a second PDMS dip-coating is applied to construct a multi-layered PDMS-ZnO-PDMS composite coating on the cotton fabrics. The multi-layer coated samples display superhydrophobic properties, with a water contact angle (CA) exceeding 160°. Additionally, the new PDMS-ZnO-PDMS@cotton fabric exhibits excellent multi-functions, including UV-blocking, self-cleaning and oil-water separation. The prepared superhydrophobic fabric can withstand a large number of abrasion cycles and 20 cycles of accelerated washing without obvious decline in the water contact angle. This facile preparation method is of low-cost, environmentally friendly, and suitable for large-scale production of a series of specialty fabrics including sports clothing. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hierarchically structured superhydrophobic radiative cooling film was fabricated. • The film integrates solar reflectance, infrared emittance and superhydrophobicity. • The film exhibits an average sub-ambient temperature drop of 12.3 °C under sunlight. • The superhydrophobicity makes the film maintain long-lasting cooling performance. • The film is promising for energy-free cooling materials towards applications. Radiative cooling without using electricity represents an ideal green solution for air-conditioning. Despite exciting progress made so far, most of the radiative cooling materials are vulnerable to outdoor contamination, which leads to decreased performance. Herein, we fabricate a hierarchically structured PVDF/PDMS porous film which integrates strong sunlight reflectance (97%), high thermal-infrared emittance (96%) and robust superhydrophobicity (160.2°). The synergy of the effective solar reflection and thermal-infrared emission enables the film to yield a sub-ambient temperature drop of 12.3 °C under strong sunlight. More importantly, the superhydrophobicity keeps the film away from contamination by self-cleaning, maintaining well the radiative cooling performance for a long-term outdoor use. Additionally, the as-obtained film shows excellent chemical durability after exposure to different pH solutions and UV light irradiation. This work provides a new strategy to integrate self-cleaning with radiative cooling, showing great potential to advance energy-free cooling materials toward real-world applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The superhydrophobic finishing strategy is environmentally-friendly and fluorine-free. • This system is suitable for multiple biomass fabrics by enzymatic hydrolysis etching. • The construction do no harm to colors and patterns of dyed fabrics. • This method can construct multifunctional fabrics for efficient self-cleaning and versatile oil-water separation. Abstract Superhydrophobic silk fabrics were prepared using an environmentally friendly enzyme-etching approach, followed by the modification with methyltrichlorosilane (MTCS) via a simple thermal chemical vapor deposition (CVD) process at 70 °C. The effects of the concentration, treatment time and temperature of enzyme on the etched surface properties were discussed. The composite superhydrophobic silk fabrics demonstrated excellent self-cleaning ability, relatively unscathed effecting their intrinsic properties such as the luster, softness, color and style of the fabrics. Furthermore, these treated fabrics demonstrated excellent mechanical durability after silane-treatment as evidenced by the cyclic abrasion and laundering tests. The composite superhydrophobic cotton fabrics have also demonstrated a high efficiency in oil-water separation. The facile technology via enzymatic hydrolysis to etch the substrate possesses extensive potential applications on various other cellulose-based substrates. [ABSTRACT FROM AUTHOR]

Rapid and efficient cleaning of oily wastewater and high viscosity crude oil spills is still a global challenge. Conventional three-dimensional porous adsorbents are ineffective for oil-water separation in harsh environment and are restricted to the low fluidity of high viscosity crude oil at room temperature. Increasing temperature can enormously improve the fluidity of viscous crude oil. Herein, the polydimethylsiloxane (PDMS) /carbon black (CB) -modified polyurethane sponge (PU) were prepared by a simple one-step dip-coating method. PDMS/CB@PU (PCPU) exhibits high adsorption capacity to various oils and organic liquid (28.5–68.7 g/g), strong mechanical properties (500 cycles at 50%), outstanding reusability (100 cycles of adsorption and desorption) and excellent environmental stability due to the special PDMS/CB coating. The maximum surface temperature of PCPU sponge can reach 84.7 ℃ under 1 sunlight irradiation. Therefore, the PCPU sponge can rapidly heat and enhance the fluidity of viscous crude oil, significantly speeding up the viscous oil recovery process with the maximum adsorption capacity of 44.7 g/g. In addition, the PCPU sponge can also combine with the vacuum pump to realize the continuous and rapid repair of viscous oil spills from the seawater surface. In consideration of its simple preparation, cost-effectiveness and high oil absorption ability, this solar-assisted self-heating adsorbent provides a new direction for large-scale cleanup and recycling of viscous crude oil spill on the seawater surface. [Display omitted] • Robust superhydorphobic sponge enables the selective separation of various emulsion. • Good photothermal conversion ability endows the rapid recovery of viscose oil spill. • Composite sponge realizes continuous, high absorption ability of viscose crude oil. • Optimized sponge achieves sustainable separation ability under harsh environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Superhydrophobic PFe-PCS with micro/nano structures were rationally constructed. • Porous PFe -PCS sample exhibits excellent mechanical properties and durability. • Flexible PFe -PCS sample would firmly adhere on curve magnetic substrates. • P-Fe -PCS shows efficient and stable anti-wetting and photothermal performance. • PFe -PCS demonstrates excellent passive anti-icing & active deicing ability. The formation and accumulation of ice can lead to severe economic loss or even loss of life. To prevent these losses, there has been rapid development in icephobic materials in recent years. To deal with various icing conditions and different types of components, it is highly desirable to develop a surface that possesses both passive anti-icing and active deicing functions. However, so far there is no suitable solution for anti-icing material with adequate durability, low cost, and simplicity in fabrication that can also be turned into active deicing when necessary. Here, we demonstrate a magnetically responsive and flexible superhydrophobic photothermal film (PFe-PCS) consisting of polydimethylsiloxane (PDMS), iron powder (Fe), and candle soot (CS). The film displayed both passive anti-icing and active deicing performances by a simple approach without using fluorine-containing chemicals. The film consists of two superhydrophobic layers that can trap two air layers in the micro/nano structures. As a result, the freezing time is 4.7 times of that of bare substrate. Such designed surface structure not only displays a significant delay in water freezing time, but also minimizes heat loss by keeping the heat within the top surface during photothermal heating. The accumulated ice can be immediately melted in 237 s and the melted water can be rapidly rolled off. The PFe-PCS film can be applied to substrates with complex shapes including curved substrates via magnetic force. More importantly, the PFe-PCS film displayed excellent stability when exposed to strong acid, base, salt solutions and liquid nitrogen. The superhydrophobicity and anti-icing performances were well retained after 320 cycles sandpaper abrasion, 3 h water flow impact, and cyclic icing/deicing. This work originated the concept of double layered surface structure for both passive anti-icing and active de-icing. The film is robust and self-healing, making it potentially applicable for ice prevention and removal for various shaped components. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effective and low-consumption foam finishing strategy for multifunctional fabrics. • Superhydrophobic coating with micro/nano structures is rationally constructed. • Robust PDMS-based coating exhibits excellent mechanical properties and durability. • Rational PDMS-based coating strategy realizes on-demand special wettability. • Wetting micropattern and directional water transportation activity is demonstrated. The technologies of superhydrophobic finishing normally involve harmful reagents such as fluorine-containing materials and organic solvents. Non-toxic, environmentally friendly, and large-scale applicable preparation methods for superhydrophobic finishing remain a considerable challenge towards practical applications. In this paper, we proposed a superhydrophobic foam finishing method with a low liquid-carrying rate. This finishing solution is totally water-based without the use of any organic solvents or fluorine-containing materials. Based on the characteristics of low liquid-carrying rate, this method can save nearly 60% of the solution consumption. In addition, multifunctional superhydrophobic fabrics, such as hydrophobic patterns and Janus fabrics, can be fabricated by this foam finishing method. Excellent properties such as superhydrophobicity, anti-fouling, and directional water transportation could be achieved by controlling the amount of superhydrophobic foams. Compared with other finishing technologies, the foam finishing method has the advantages of being facile, rapid in preparation, environmentally friendly, and applicable for large-scale production. This technology could be applied on various substrates and achieve rapid preparation for superhydrophobic surface, Janus surface, and double-sided heterochromatic superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]