Sandpaper Abrasion Research Articles

Eco-Friendly Fabrication of Transparent Superhydrophobic Coating with Excellent Mechanical Robustness, Chemical Stability, and Long-Term Outdoor Durability.

Surfaces that possess both superhydrophobicity and high transparency at the same time recently have attracted extensive attention in outdoor applications. However, fabrication and application of transparent superhydrophobic coating usually face following challenges: the micro-nano hierarchical structure required for superhydrophobicity usually leads to a decrease in the light transmittance due to its light trapping effect; fluorine-containing materials used in the preparation of superhydrophobic surfaces are potentially harmful to humans and the environment; and the superhydrophobic surface is easily destroyed by external factors. In this work, a transparent superhydrophobic coating was fabricated via an inexpensive and eco-friendly two-step method, that is, dipping glass substrate into the polydimethylsiloxane/SiO2 suspension followed by calcination treatment. The prepared coating showed superhydrophobicity with a water contact angle of 164° and a sliding angle less than 1.0°. In the visible light region with the wavelength range of 300-900 nm, the maximal transmittance of the superhydrophobic coating was ∼91.4%, which is higher than that of the untreated glass substrate (∼90.9%). Moreover, the coating can maintain superhydrophobicity and high transmittance after sandpaper abrasion, water flow impact, immersion in strong acid/alkaline solution, UV irradiation, and long-term outdoor exposure. We believing that the coating has huge potential value in outdoor applications.

Preparation of silicone-PCL composite particles with hierarchical structure and the super-hydrophobic fabrics via directly electrostatic spraying

Herein, microspheres with a rough structure were prepared via electrostatic spraying, using a spray solution prepared by dissolving poly(ε-caprolactone) (PCL) and ladder-like fluorinated polysilsesquioxane (F-PH-LPSQ) blends in chloroform. The effects of concentration, voltage, flow rate, receiving distance and blending ratio on the morphology and particle size distribution of the microspheres were investigated. The microsphere spray coatings prepared under different blending ratios were tested: the results demonstrate that the contact angles of the coatings all exceeded 150°, the rolling angles were all smaller than 1° and the adhesion forces were all <51 μN, thus displaying excellent superhydrophobicity. The formation mechanism of the ‘roughened’ microsphere morphology was explored by analysing the energy dispersive spectroscopy results and element content of the protruding and pitted parts of the sprayed particles. The spraying and blending ratio was optimised and determined to be 1.0:0.4. Subsequently, the PCL/F-PH-LPSQ microspheres were directly sprayed and coated with the developed spray solution via electrostatic spraying. The water contact angle of the finished cotton fabric was found to be ≥160°, which provided excellent hydrophobicity and self-cleaning function. Following the sandpaper abrasion and adhesion tests, the contact angle of the fabrics coated with the microspheres remained ≥155°,indicating a good mechanical stability.

Mechanically robust and superhydrophobic concrete based on sacrificial template approach

Superhydrophobic (SH) concrete with low adhesion, self-cleaning, and corrosion resistance has the potential to significantly meet the challenges of injury and fatality under various external conditions such as irradiation, chemical corrosion, and biological contamination. However, the traditional process to realize the superhydrophobicity normally brings the concern of compressive strength loss. Herein, we introduced a facile approach to fabricate the superhydrophobic concrete with mechanical robustness based on the sacrificial template strategy. The concrete exhibits prominent water-repellency and admirable compressive strength simultaneously. The superhydrophobicity was well maintained after cyclic robustness evaluations, including sandpaper abrasion, knife scratch, water impacting, corrosive solution immersion, and UV radiation. The superhydrophobic concrete also exhibits broad-spectrum self-cleaning capability, such as easy removal of common dust, bacteria detachment, and resistance of ice formations. We believe that the SH concrete can potentially address the mechanical robustness and long-term water repellency towards the real applications in the future.

Facile Fabrication of Fluorine‐free Silica‐based Superhydrophobic Coating Using Acid‐catalyzed Silica Adhesive

AbstractEco‐friendly, easy, fast and scalable strategies for robust superhydrophobic coatings are of great significance for industrial application. Herein, a robust fluorine‐free superhydrophobic coating is prepared via spraying the mixed suspension which consist of silica nanoparticles and hydrophobic acid‐catalyzed silica sol. The adhesive which is synthesized through hydrolyzation and condensation of silane precursors (TEOS, MTMS, HDTMS) shows good compatibility with silica nanoparticles. When the mass ratio of SiO2/adhesive was 0.025 : 1, the prepared coating exhibited good non‐wettability with a WCA of 164° and a RA of 2°. Moreover, due to the hydrophobic acid‐catalyzed silica sol which bonds silica nanoparticles together, the coatings also demonstrate well mechanical robustness. After 60 g sand impacted on the surface of as‐prepared coating from a height of 1 m, the surface still showed superhydrophobicity with a WCA of 152° and a RA of 6°. And the as‐prepared coating could endure the sandpaper abrasion for 80 cm. Furthermore, the adhesion of as‐prepared coatings to substrates can reach the highest 5 A level. The current work provides an easy and promising approach to meet the challenges in practical applications simultaneously posed by the fluorine‐free, low‐cost, mechanical robustness as well as large‐scale preparation of silica‐based superhydrophobic coatings.

One-step rapid preparation of superhydrophobic peek with mechanical, and chemical stability

The superhydrophobic surface has the characteristics of self-cleaning, anti-corrosion, and drag reduction. Peek materials are resistant to corrosion, abrasion, and hydrolysis. Superhydrophobic peek combined with the two has attracted widespread interest. Herein, a fast and inexpensive method was presented to fabricate superhydrophobic peek with mechanical, chemical, high-temperature, hot-water, and high-pressure water impact stability. For the first time, the periodic fringe morphology with a micro-nano hierarchical structure was processed on the surface by a nanosecond laser so that the surface of the peek became super-hydrophobic. Robustness was promoted when performing various mechanical stability tests such as sandpaper abrasion, sonication, static pressure, and tape peel test. The superhydrophobic peek surface still had good chemical stability and had excellent repulsion to droplets with pH = 1–14. The surface was resistant to high-temperature, hot-water, and high-pressure water impact. These stated features reveal the convincing potential of the method to simultaneously address robustness, flexibility, and adaptability.

The Effect of Scarification Treatments and Seed Moisture Content on the Hardseededness of ‘Taitung No.1’ Winged Bean (Psophocarpus tetragonolobus) Seeds

Seeds of some winged bean varieties have low germination due to the presence of water-impermeable hardseeds. Seeds of ‘Taitung No.1’ winged bean had only 31% germination because the remaining 69% of seeds had a water-impermeable seedcoat. Sandpaper abrasion and sulfuric acid immersion for 15 and 25 min effectively removed hardseededness of the seeds, resulting in more than 89% germination. As seed moisture content (MC) decreased from 14.8% to 7%, the percentage of seeds with a water-impermeable seedcoat increased. Seed lots with 14.8%, 11%, 9%, and 7% MC had 7%, 38%, 56%, and 78% of hardseeds, respectively, on day 7 in the germination test. It was found that the hilum was responsible for water loss from the whole seed, and the seedcoats began to become water-impermeable at 12% MC. The lens and micropylar regions were initial water entry sites in the Vaseline-blocking experiment.

Preparation of silica-epoxy superhydrophobic coating with mechanical stability and multifunctional performance via one-step approach

Functionalized nanoparticles can provide the required rough structures and properties, which are an effective way to construct superhydrophobic surfaces. Yet, these surfaces have problems of complicated fabrication and poor adhesive strength. Based on the above problems, the hydrophilic SiO2 nanoparticles are modified with low-surface-energy 1 H, 1 H, 2 H, 2 H-perfluorodecyltrimethylsilane (FAS-17) to synthesize fluorosilane-modified SiO2 (FS) nanoparticles. Furthermore, epoxy resin (EP) containing stable benzene ring and ether bond was introduced as adhesive and anti-corrosion substance to form the superhydrophobic FSEP coating by a one-step approach. The as-prepared coating exhibits high water repellency and adhesion on various substrates, with water contact angle of 162.0º and rolling angle of 2.6º. The coating can withstand 550 cm sandpaper abrasion and resist water droplets with different pH values, showing good mechanical and chemical stability. Additionally, it possesses good durability after weathering in air for 30 d or immersing in saline for 14 d. Moreover, the coating demonstrates excellent multifunctional performance in anti-corrosion, drag reduction and self-cleaning, and its mechanisms of multifunctional applications are analyzed and revealed in detail. It is noteworthy that the corrosion current is decreased by 3 orders of magnitude and the drag reduction rate is enhanced by 28.06 %, after spraying the FSEP coating on the aluminum alloy. This work establishes multifunctional superhydrophobic coating through a simple and effective one-step approach, which will further expand the production scale of superhydrophobic coatings and facilitate their practical applications.

Facile fabrication of robust and photo-thermal super-hydrophobic coating with efficient ice removal and long-term corrosion protection

Multifunctional integration is an essential feature to broad the practical application of artificial super-hydrophobic coating in numerous fields. Herein, a passive anti-icing and active photo-thermal deicing super-hydrophobic coating with excellent mechanochemical durability, self-healing and long-term corrosion protection performances has been developed by a facile and environmentally friendly heterogeneous hybrids approach. The prepared coating exhibits excellent super-hydrophobicity with CAs up to 161.9°, SAs is only 4.2° and the adhesive force value of microdroplets is ∼16.8 ± 0.6 μN. The composite coating holds its prominent water repellency even after various extreme treatments, including high-low temperature alternation, 60 m sandpaper abrasion, kneading stability and corrosive medium immersion. Moreover, the coating also presents remarkable self-cleaning properties both in air or oil even after mechanical abrasion and significantly healable capabilities against O2 plasma etching. Furthermore, the influence mechanism of the heterogeneous hybridization on thermal property and corrosion resistance of the coating were systematically analyzed. In addition, utilizing the superior water repellence and the photo-thermal performance, the coating could efficiently delay the freezing time and active deicing after 808 nm NIR laser irradiate. Therefore, the multifunctional integrated super-hydrophobic coating will be promising for several industrial fields.

Electrodeposition of silane/reduced graphene oxide nanocomposite on AA2024-T3 alloy with enhanced corrosion protection, chemical and mechanical stability

Hydrophobic silane/reduced graphene oxide (rGO) nanocomposites were successfully constructed on an AA2024-T3 aluminum alloy surface using a facile co-electrodeposition process. The composition and morphology were characterized by ATR-FTIR, XRD, Raman spectroscopy, EDX, XPS and SEM. The results revealed that the implanted GO nanosheets were partially reduced and successfully covalently bonded with silanol groups to fabricate a more compact and denser coating. Electrochemical measurements demonstrated that the electrodeposited silane/rGO nanocomposite markedly decreased the corrosion rate of the AA2024-T3 alloy in 3.5 wt% NaCl solution. The protection efficiency was maintained over 96% after 120 h of exposure, presenting excellent chemical stability. Meanwhile, a sand paper abrasion test was performed to evaluate the mechanical robustness and the contact angle was reduced by only 4.5° after 150 abrasion cycles. The excellent anti-corrosion property and mechanical robustness, along with the feasible electrodeposition procedure, show its great potential for industrial applications.

A Silicone Resin Coating with Water-Repellency and Anti-Fouling Properties for Wood Protection.

The strong hygroscopicity of wood greatly shortens its service life. Here, a simple impregnation modification approach was used to construct superhydrophobic silicone resin coatings on wood surfaces. Briefly, with hydrofluorosilicone oil (HFSO), tetramethyl tetravinyl cyclotetrasiloxane (V4), and hydrophobic SiO2 from industrial production as raw materials, superhydrophobic wood samples (water contact angle ~160.8°, sliding angle ~3.6°) can be obtained by simply dipping the wood in the HFSO/V4/SiO2 modifier solutions. As a result, the superhydrophobic silicone resin coating constructed on the wood surface still has good water repellency after finger touching, tape peeling, and sandpaper abrasion. When the mass ratio of HFSO to V4 is 2:1, the water absorption of the resulting wood after soaking in water for 24 h is only 29.2%. Further, the resulting superhydrophobic wood shows excellent anti-fouling properties. Finally, we believe that the impregnation modification method proposed in this study can be applied to the protection of cellulose substrates.

A Robust Superhydrophobic Smart Coating with Reversible Thermochromic and Photochromic Property

Both thermochromic and photochromic coating have attracted many attentions due to their widely applications, but the low stability is a big obstacle. Inspired by the lotus leaf, to endow the chromic coating with superhydrophobicity is a possible solution. In this research, a dual response coating was prepared by adding photochromic and thermochromic particles simultaneously. The prepared sample demonstrated at least four-state color switching, which can be successfully used in tactile imaging, multi-color fabric, erasable record, and security labels. The superhydrophobicity was achieved by introducing vinyl-terminated polydimethylsiloxane, which not only offers low surface energy but also can cross-link with the particles to increase the adhesion. Thus, the prepared sample maintained superhydrophobicity after various kinds of destruction (such as sandpaper abrasion, corrosive liquid attack, ultrasonic treatment, UV irradiation, and high-speed drops/turbulent jets impact). Even though the superhydrophobicity can be destroyed by plasma etching, it can be recovered after 12 h at room temperature.

Coupled Bionic Drag-Reducing Surface Covered by Conical Protrusions and Elastic Layer Inspired from Pufferfish Skin

Inspired by the drag-reducing properties of the cone-like spines and elastic layer covering the pufferfish skin, important efforts are underway to establish rational multiple drag-reducing strategies for the development of new marine engineering materials. In the present work, a new drag-reducing surface (CPES) covered by conical protrusions (sparse "k-type" with rough height k+ = 13-15) and an elastic layer are constructed on copper substrate via a hybrid method, combining the sintering and coating processes. The drag-reducing feature of the prepared CPES biomimetic surface is achieved by rheometer and particle image velocimetry (PIV) experiments. To comprehensively investigate its drag reduction mechanism, the porous copper substrate (PCS), copper substrate (CS), conical protrusion resin substrate (CPRS), and conical protrusion porous copper substrate (CPPCS) were used for a comparative analysis. In laminar flow, we discovered that the conical protrusion structure and wettability of the elastic surface coupling affect the CPES sample's drag-reducing performance (7-8%) and that the interface produced slip to reduce the viscous drag. In turbulent flow, the CPES biomimetic surface exhibits an 11.5-17.5% drag-reducing performance. Such behavior was enabled by two concurrent mechanisms: (i) The conical protrusions as vortex generators enhance the number of vortices and the wake effect, enabling faster movement of downstream strips, reducing viscous drag; (ii) The conical protrusion elements break and lift large-scale vortices to produce numerous small-scale vortices with low energy, effectively weakening perturbations and momentum exchange. Additionally, the elastic layer shows high adhesion and stability on copper substrate after sandpaper abrasion and water-flow erosion tests. The copper substrate surface formed by the sintering method is also covered with dense porous structures, which gives the elastic layer and conical protrusions excellent combined robustness. Our findings not only shed new light on the design of robust drag-reducing surfaces but also provide new avenues for underwater drag reduction in the field of marine applications.

Designing Photothermal Superhydrophobic PET Fabrics via In Situ Polymerization and 1,4-Conjugation Addition Reaction.

This study demonstrates a simple and fast method to integrate superhydrophobicity, UV protection, and photothermal effect onto PET fabrics. The surface of PET fabric forms a hierarchical rough structure through in situ oxidative polymerization of the pyrrole (Py). The 1,4-conjugate addition reaction between pentaerythritol tetraacrylate, 3-aminopropyltriethoxysilane, and octadecyl acrylate not only endows the PET fabric with superhydrophobicity but also forms a cross-linked network structure which improves the stability of multifunctional coatings on the surface of the PET fabric. In addition, the wettability of the prepared PET fabric is investigated by adjusting the Py monomer and octadecyl acrylate concentration. The results reveal that the prepared PET fabrics exhibit obviously superhydrophobic behavior with a contact angle of 155.8°. The surface temperature of the superhydrophobic PPy/PET fabric can rise to 91 °C under a simulated sunlight which is much higher than the pristine PET fabric, while reaching basically the same steady-state in five heating/cooling cycles. The prepared PET fabric also possesses excellent self-cleaning, UV shielding, and solar light absorption performances. Furthermore, the superhydrophobic PET fabric exhibited excellent stability against 180 °C high temperature, strong UV radiation, different pH solutions and organic solvent erosion, 8 h washing tests, and 25 sandpaper abrasion cycles. These findings provide a path for the future development of multifunctional fabrics using fluorine-free environmentally friendly materials.

How does surfactant affect the hydrophobicity of wax-coated wood?

To investigate the role of surfactants in affecting the hydrophobicity of wax-coated wood, six groups of wax emulsions with different surfactant contents (0, 5%, 10%, 20%, 40%, and 60%) were prepared by ultrasonication to modify wood. The hydrophobicity and moisture buffering capacity of the wax-coated wood as well as the mechanical stability of wax coating on wood surface were characterized by dynamic contact angle measurement, moisture buffering experiment, sandpaper abrasion test, and simulated rain test. Combined with the analysis of the surface microstructure and chemical composition by SEM and XPS, the relationship between the surfactant content and the properties of the wax-coated wood was clarified. The results indicate that the surfactants not only reduced the long-term hydrophobicity of wax-coated wood, but also improved the mechanical stability of wax coating. As the content of surfactants increased from 5% to 60%, the water contact angle decreased from 145.7° to 135.5°. The droplets spread quickly on the wood surface, and the decrease in contact angle after the rain test reduced from 4.8% to 1.3%. However, the effect of surfactant content on the moisture buffering capacity of the wax-coated wood first increased and then decreased. The change in the properties of wax-coated wood is directly related to the change in the surface micro/nano rough structure and chemical composition caused by the surfactant content.

Eco‐friendly UV‐curable polyurethane‐silica superhydrophobic coating with superb mechanical durability

AbstractHerein, a facile, scalable, and cost‐effective method was used to fabricate eco‐friendly superhydrophobic UV‐curable polyurethane‐silica nanocomposite coating with promising physicomechanical properties. Fluorinated UV‐curable polyurethane dispersion was synthesized and used as the binder of the superhydrophobic coating along with hydrophobically modified silica nanoparticles as textured topography. The chemical structures of the employed silica nanoparticles, prepared UV‐curable polymer, and superhydrophobic coating were thoroughly studied by FTIR analysis. It has been revealed that the prepared SH coating possesses well‐defined micro/nano‐scale roughness, high contact angle (159°), and low sliding angle (1.5°), which can be applied onto various substrates. Also, the exceptional durability of the fabricated coating against sandpaper abrasion (over 80 m) without losing its superhydrophobicity revealed the high capability of the prepared waterborne coating to be used in harsh practical applications. Additionally, due to the highly cross‐linked structure of the prepared SH coating, the applied coating could maintain its integrity even after 30 days of immersion in different organic solvents. Moreover, the prepared coatings showed substantial potential for use in self‐cleaning and oil/water separation fields (&gt; 98% efficiency after 15 cycles of oil/water separations). We are convinced that the prepared hybrid coating could offer a practical approach for fabricating of superhydrophobic materials as promising nominates for disparate fields.

A Superhydrophobic Alkali Activated Materials Coating by Facile Preparation

Alkali activated materials (AAMs) were considered as economical and environmentally friendly that have attracted incrementally attention as green coating materials. However, alkali activated materials were inclined to be infiltrated and ruined by harmful ions in water due to their hydrophilicity. And the ordinary ways of construct superhydrophobic coatings were costly, complex and need fluorine material. The superhydrophobic surfaces were fragile owing to the super-hydrophobicity of materials were controlled to surface merely. In this work, a facile, convenient and economical strategy to synthesize alkali activated slag materials (AAS) superhydrophobic coatings with excellent water repellence was developed. Herein, the hydrolysis and polymerization of triethoxy (octyl)silane (TTOS) were applied for generating micro/nanostructures to construct a three-dimensional overall superhydrophobic alkali activated slag materials coating. The water contact angle (CA) about surfaces and bottoms of superhydrophobic alkali activated slag materials coatings were 150.2°, 152° and the water rolling angle (SA) of surfaces and bottoms were 5°, 4° respectively. Besides, the superhydrophobic alkali activated slag materials coatings demonstrated excellent mechanical abrasion effect that still maintain super-hydrophobicity after sandpaper abrasion stand. Super-hydrophobicity of coatings could be regenerated by simple sandpaper rubbing when they were attacked chemically. Concisely, the superhydrophobic alkali activated slag materials coatings were show the benefit of affordable and feasibility so that they have the potential for expandable industrial promotion.

Fluoropolymer-based hybrid superhydrophobic nanocomposite coating with antifouling and self-cleaning properties for efficient oil/water separation

The production of industrial and domestic effluents possessing oily contaminated water has become a global concern as a result of environmental contamination and pollution. Newly synthesized organic-inorganic hybrid nanocomposites with special wetting and anti-wetting properties have been adopted in recent times to address this problem. However, this method has faced a few setbacks in curbing the situation, which leaves the problem persistent. In order to realize the full potential of hybrid composites in combating oil/water contamination, we synthesize a robust organic-inorganic superhydrophobic hybrid nanocomposite containing Polyvinylidene fluoride (PVDF) and silicon hydroxide (SiO2) to coat cellulose filter paper for effective and efficient separation of oil/water mixtures. With a simple dip-coating technique, the superhydrophobic hybrid composite obtain a superhydrophobicity with a water contact angle as high as 161˚ on the filter paper. The coated membrane possessed a robust mechanical property as well as chemical stability which withstands a sandpaper abrasion test of up to 80 cycles and could retain its superhydrophobicity in acidic, neutral and alkaline media after 24hrs of immersion respectively. Moreover, the coated surface possessed nanopores which allows it to be used in oil water separation applications both under pressure and gravity with a separation efficiency of up to 99.7 % and can also be recycled many times for use. The excellent antifouling and self-cleaning ability of the coated membrane also prevents the adhesion of contaminants from the surface. The outstanding performance of the facilely and cost-effective fabricated superhydrophobic hybrid composite reveals a great potential for curbing the problems of oil contamination while addressing some existing barriers to the full potential realization of hybrid composites.

Bio-Inspired Hollow Carbon Microtubes for Multifunctional Photothermal Protective Coatings.

Solar energy-facilitated materials are promising to solve energy problems by converting clean solar energy to thermal energy. However, heat loss of photothermal materials still limits the photothermal conversion phenomenon. Herein, we designed bio-inspired hollow carbon microtubes (HCMTs) by one-step carbonization of renewable cotton fibers, which can avoid the complex preparation procedures of the template method. Similar to polar bears, the hollow construction can efficiently reduce heat loss, which improves the utilization of light and photothermal property. The HCMTs can be applied on a variety of substrates to obtain multifunctional photothermal protective coatings. The temperature of the coating can rapidly warm up to 97.7 °C under 1 kW/m2 sun irradiation. In addition, the coatings show excellent superhydrophobic property (CA of 161.5 ± 0.9°), which can prevent the adhesion of the contaminant and maintain the long-time photothermal property of the surface. Also, the coating is able to withstand sandpaper abrasion, repeat tape-peeling, and tribological friction without losing superhydrophobic properties, indicating remarkable mechanical stability. Furthermore, the coating can withstand high-temperature calcination (400 °C), long-time UV radiation, and corrosive liquid erosion, which exhibits prominent chemical stability. More importantly, the combination of active deicing and passive anti-icing of the coating can effectively prevent the formation and accumulation of ice on the surface. The outstanding environmental adaptability can greatly extend its lifespan and meet the long-term service conditions.

Preparation of Iron Ore Tailings-Based Superhydrophobic Coatings.

In this study, ball mill pretreated iron ore tailings were modified with tetraethoxysilane (TEOS) and hexadecyltrimethoxysilane (HDTMS) to obtain iron ore tailings/polysiloxane (IOT/POS) superhydrophobic powders, which were subsequently mixed with chloroprene rubber solution (CRS) to prepare durable superhydrophobic composite coatings. The effect of HDTMS amount and reaction time on the wettability of the superhydrophobic powder was investigated. The influence of the superhydrophobic powders concentration on the wettability of the composite coatings as well as the degree of damage of the superhydrophobicity of the composite coating was analyzed by using the sandpaper abrasion and tape peeling tests. Further, SEM and FTIR were used to analyze the formation mechanism of the IOT/POS superhydrophobic powders and coatings. The results showed for an HDTMS amount of 2.5 mmol and reaction time of 4 h, the contact angle of the IOT/POS powder was 157.3 ± 0.6°, whereas the slide angle was determined to be 5.9 ± 0.8°. For an IOT/POS powder content of 0.06 g/mL in CRS, the contact angle value of the superhydrophobic composite coating was 159.2 ± 0.5°, whereas the slide angle value was 5.5 ± 0.8°. The superhydrophobic composite coating still maintained the superhydrophobicity after the sandpaper abrasion and tape peeling tests, which indicated the iron ore tailings solid waste has the potential to prepare superhydrophobic coatings.

A robust superhydrophobic anti-icing/de-icing composite coating with electrothermal and auxiliary photothermal performances

Passive anti-icing and active anti-icing/de-icing were two major strategies to suppress icing on surfaces. Combining these two strategies and making full use of various energies can greatly improve anti-icing efficiency. In this study, a multifunctional anti-icing/de-icing coating with superhydrophobic passive anti-icing and electrothermal/photothermal active de-icing properties was proposed. Fluorinated epoxy resin and carbon/PTFE particles were used to prepare the multifunctional anti-icing/de-icing coating, which exhibited superhydrophobicity with water contact angle greater than 155° and conductivity higher than 40 S/m. The robust superhydrophobic property was demonstrated by repeated sandpaper abrasion and tape peeling tests. Moreover, both electricity and solar energy can be adopted for heating the surface and de-icing, showing efficient electrothermal/photothermal and anti-icing/de-icing properties. In addition, the synergistic icephobic mechanism was validated by characterizing the different freezing states of water droplets on surfaces: repelling droplets before freezing occurred, delaying icing during the freezing process and significantly reducing the ice adhesion after freezing via the self-generated micro-scale water film by heating. This study provided a new way to manufacture functional materials for practical anti-icing/de-icing applications.