Search Results (264)

The bioinspired superhydrophobic surfaces have demonstrated many fascinating performances in fields such as self-cleaning, anti-corrosion, anti-icing, energy-harvesting devices, and antibacterial coatings. However, developing a low-cost, feasible, and scalable production approach to fabricate robust superhydrophobic surfaces has remained one of the main challenges in the past decades. In this paper, we propose an uncommon method for the fabrication of a durable superhydrophobic coating on the surface of the glass slide (GS). By utilizing the screen printing method and high-temperature curing, the epoxy resin grid (ERG) coating was uniformly and densely loaded on the surface of GS (ERG@GS). Subsequently, the hydrophobic silica (H-SiO₂) was deposited on the surface of ERG@GS by the impregnation method, thereby obtaining a superhydrophobic surface (H-SiO₂@ERG@GS). It is demonstrated that the micro-grooves in ERG can provide a large specific surface area for the deposition of low surface energy materials, while the micro-columns can offer excellent protection for the superhydrophobic coating when it is subjected to mechanical wear. It is important to note that micro-columns, micro-grooves, and nano H-SiO₂ jointly form the micro–nano structure, providing a uniform and robust rough structure for the superhydrophobic surface. Therefore, the combination of a micro–nano rough structure, low surface energy material, and air cushion effect endow the material with excellent durability and superhydrophobic property. The results show that H-SiO₂@ERG@GS possesses excellent self-cleaning property, mechanical durability, and chemical stability, indicating that this preparation method of the robust superhydrophobic coating has significant practical application value. Full article

Metal materials are widely used in power grid infrastructure, but they are prone to metal corrosion due to long-term exposure to various environmental conditions, resulting in significant losses. The existing superhydrophobic coatings have good anti-corrosion performance, but poor wear resistance. Therefore, it is extremely important to improve the wear resistance of superhydrophobic coatings. In this study, a kind of fluorine-modified SiO₂ particle was prepared with pentafluorooctyltrimethoxysilane (FAS-13) as the low surface energy modifier, following the fabrication of a superhydrophobic coating on metal substrate via a PDMS-doped spray deposition method to reinforcement wear resistance property. XPS, FT-IR and Raman spectra confirmed the successful introduction of FAS-13 on SiO₂ particles, as evidenced by the characteristic fluorine-related peaks. TGA revealed that the fluorine modified SiO₂ (F-SiO₂) particles exhibited excellent thermal stability, with an initial decomposition temperature of 354 °C. From the perspective of surface morphology, the relevant data indicated a peak-to-valley height difference of only 88.7 nm, with Rq of 11.9 nm and Ra of 8.86 nm. And it also exhibited outstanding superhydrophobic property with contact angle (CA) of 164.44°/159.48°, demonstrating remarkable self-cleaning performance. And it still maintained CA of over 150° even after cyclic abrasion of 3000 cm with 800 grit sandpaper under a 100 g load, showing exceptional wear resistance. In addition, it was revealed that the coated electrode retained a high impedance value of 8.53 × 10⁸ Ω·cm² at 0.1 Hz after 480 h of immersion in 5 wt% NaCl solution, with the CPE exponent remaining close to unity (from 1.00 to 0.97), highlighting its superior anti-corrosion performance and broad application prospects for metal corrosion prevention. Full article

Titanium dioxide (TiO₂) thin films were deposited by DC magnetron sputtering and subsequently treated in hot water at 50, 70, and 95 °C for 72 h to investigate the influence of low temperature on their structural optical and functional properties. XRD analysis revealed a progressive transformation from amorphous to anatase phase with increasing treatment temperature, accompanied by an increase in crystallite size from 5.2 to 15.1 nm. FT-IR spectroscopy confirmed enhanced surface hydroxylation and contact angle measurements showed a decrease from 77.4° to 19.7°, indicating a significant improvement in superior wettability. The transmittance spectroscopy revealed a slight narrowing of the optical band gap from 3.34 to 3.21 eV, consistent with improved visible-light absorption. Photocatalytic tests using the Resazurin indicator demonstrated that the film treated at 95 °C exhibited the highest activity, achieving a bleaching time of 245 s three times faster than treated at 50 °C and twice as fast as treated at 70 °C. Under low-intensity solar irradiation, the same sample achieved complete E. coli inactivation within 90 min. These improvements are attributed to increased crystallinity, surface hydroxyl density, and enhanced ROS generation. Overall, this study demonstrates that mild hot-water treatment is an effective, substrate-friendly route to enhance TiO₂ film wettability and multifunctional performance, enabling the fabrication of self-cleaning and antibacterial coatings on fragile materials such as plastics and textiles. Full article

Superhydrophobic surfaces have gained considerable attention due to their ability to repel water and reduce surface adhesion, and they are now widely applied for self-cleaning, anti-fouling, anti-icing, and corrosion resistance purposes. In this study, either a computer numerical control (CNC) machine or photolithographic techniques were employed to fabricate molds with microwells, followed by soft lithography to obtain a polydimethylsiloxane (PDMS) micropillar array. An etching process was then carried out. It was found that, as etching time increased, the diameters of micropillars decreased, leading to a decrease in the solid fraction of the composite surface and increases in contact angles. When the ratios of spacing to diameter (W/D) and of height to diameter (H/D) both exceeded 1.5, the contact angle was found to exceed 150° and the original PDMS micropillar surface with a contact angle of around 135° became superhydrophobic. A drastic decrease in sliding angle was also observed at this threshold. Changes in contact angles with different W/D values were in good agreement with values calculated using the Cassie–Baxter equation, and the droplet state was verified by a pressure balance model. Meanwhile, the PDMS etching rate when using acetone as the solvent was approximately 6–8 times faster than that when using 1-Methyl-2-pyrrolidone (NMP), a result which is comparable to data in the literature. Full article

Developing sustainable, high-performance biomass composites is crucial for replacing non-renewable structural materials. In this study, a “bamboo steel” composite was fabricated using a multilevel modification strategy involving alkali pretreatment, toughened resin impregnation, and surface functionalization. Bamboo fibers were treated to remove hemicellulose and lignin, enhancing porosity and interfacial bonding. The bamboo scaffold was subsequently impregnated with a thermo-plastic polyurethane-modified epoxy resin to create a robust, interpenetrating network. The optimized composite (treated at 80 °C) exhibited a flexural strength of 443.97 MPa and a tensile strength of 324.14 MPa, demonstrating exceptional stiffness and toughness. Furthermore, a superhydrophobic coating incorporating silica nanoparticles was applied, achieving a water contact angle exceeding 150° and excellent self-cleaning properties. This work presents a scalable strategy for producing bio-based structural materials that balance mechanical strength with environmental durability. Full article

Silica-based multifunctional coatings hold great promise for applications in optical devices, lenses, and solar panels. Herein, we report a facile, low-temperature route to integrate super-hydrophobicity with high transparency and low haze. By precisely controlling particle gradation and applying fluorine passivation, a multi-scale structure with micro-scale uniformity and nano-scale asperity was constructed. This unique architecture, combined with low surface energy, effectively reduces light scattering and enhances air trapping. Consequently, the coated glass achieves a high optical transmittance of 95.24% with a low haze of 0.97%, alongside a water contact angle of 153° and a sliding angle of 3°. The coating also exhibits distinct anti-reflection (an improvement of ~5.0% relative to the bare substrate) and self-cleaning properties. Furthermore, it demonstrates impressive robustness and durability, withstanding extreme conditions including cryogenic temperatures (−50 °C), hygrothermal environments, and long-term outdoor exposure. This work demonstrates the versatile potential of our strategy for fabricating highly transparent and superhydrophobic surfaces. Full article

Femtosecond laser has been widely utilized in functional microstructural surfaces for applications such as anti-reflection, radiative cooling, and self-cleaning. However, achieving high-efficiency manufacturing of high-consistency functional microstructures (with feature sizes ~1 μm) over large areas remains a challenge. Here, we report a femtosecond laser temporal and spatial modulation technique for fabricating large-area anti-reflective microholes on magnesium fluoride (MgF₂) windows. The beam was transformed into a Bessel beam to extend the Rayleigh length, enabling the fabrication of microhole arrays with sub-micron precision and surface roughness variations within 10 nm over a 6 μm focal position shift range (5–11 μm). By modulating MHz burst pulses, the aspect ratio of the microholes was increased from 0.3 to 0.7 without compromising a processing speed of 10,000 holes per second. As a proof of concept, large-area anti-reflective microholes were fabricated on a 20 mm × 20 mm surface of the MgF₂ window, forming a nanoscale refractive index gradient layer and achieving a transmittance increase to over 98%. This method provides a feasible solution for the efficient and high-consistency manufacturing of functional microstructures over large areas. Full article

Bio-inspired superhydrophobic coatings have garnered significant attention in recent years due to their potential in creating self-cleaning and anti-icing surfaces. Drawing inspiration from natural systems such as lotus leaves and insect wings, these coatings leverage hierarchical nanostructures to achieve extreme water repellency and low surface adhesion. This review explores recent advances in the design, fabrication, and functional performance of bio-inspired superhydrophobic materials, with a focus on hierarchical micro/nanostructured surfaces. We discuss the underlying mechanisms of wettability, the role of surface chemistry, and the integration of durable nanostructures for enhanced durability. Additionally, the paper discusses the latest progress in scalable manufacturing techniques, environmental adaptability, and multifunctional performance, particularly in self-cleaning and anti-icing applications. Emerging trends, such as stimuli-responsive surfaces and smart coatings, are also examined to provide a comprehensive overview of the field. This review discusses the challenges and future directions for translating laboratory-scale innovations into real-world applications, particularly in aerospace, automotive, energy, and infrastructure sectors. Full article

Current demands in the field of functional textiles include the integration of specific characteristics, such as self-cleaning, antimicrobial efficacy and possible wound healing properties. Green synthesis of nanoparticles represents a promising strategy to address these challenges, combining biocompatibility and ecological safety with effective antimicrobial and antioxidant performance. In this study, silver nanoparticles (AgNPs) have been synthesized using different ratios of Crataegus monogyna extract: AgNO₃. Physically stable AgNPs with spherical shape, particle main diameters ranging from 61.9 to 85.4 nm and appropriate polydispersity indices were produced. Crataegus monogyna presented high phenolic content (30.58 ± 2.20 mg/g) and strong antioxidant activity (96 ± 1.6 µmol TE/g). The obtained nanoparticles were characterized by TEM, EDX, and XRD analysis. When applied to cotton and wool textiles, the AgNPs adhered uniformly, caused minimal colour change, and exhibited enhanced antimicrobial activity against bacterial and fungal strains compared to other plant-derived AgNPs, with values between 8 and 13.5 mm. The treated textiles demonstrated strong performance against Staphylococcus aureus with inhibition zones of 11 ± 0.53 for cotton and 13.5 ± 0.42 for wool. These findings highlight the potential of Crataegus monogyna-based AgNPs as effective and fabric-compatible antimicrobial agents. Full article

To enhance the mechanical performance and surface hydrophobicity of flat thin-sheet materials, we have developed a facile, environmentally benign, and low-cost synthesis strategy for fabricating a robust waterborne superhydrophobic coating with excellent mechanical reinforcement, via simple spray coating using a non-fluorinated material system (waterborne silicone–acrylic copolymer and silica sol). The functional coating exhibited excellent hydrophobicity (water contact angle: 150°) regardless of the compound of the substrates, which is primarily ascribed to the presence of abundant low-surface-energy methyl groups on the coating’s surface, along with the three-dimensional hierarchical network structure formed via the cross-linked silica network. Owing to the stable cross-linked structure and strong interfacial bonding between the acrylic polymer and silica network, the composite coating exhibited exceptional mechanical reinforcement, coupled with ultrahigh mechanical and chemical stability. Specifically, the maximum flexural fracture load of the modified materials increased from 119 N to 192 N, representing a 62.7% enhancement; similarly, the moisture-induced deflection of the samples had a significant increase from −14.5 mm to −3.01 mm, which confirmed that the mechanical properties of the modified sample and its deformation resistance under high humidity conditions have been significantly enhanced. Notably, the coating retained superior hydrophobicity and mechanical performance even after 50 abrasion cycles, as well as exposure to high-intensity UV radiation and corrosive acidic/alkaline environments. Furthermore, the composite functional coating demonstrated excellent self-cleaning and anti-fouling properties. This functional composite coating offers significant potential for large-scale industrial application. Full article

This study introduces a novel fabrication method for high-strength, self-cleaning photocatalytic membranes through the integration of hot-pressing and TiO₂/chitosan/SiO₂ nanofibers. The innovation of this research lies in the hot-pressing technique, which significantly enhances the mechanical properties and photocatalytic efficiency by improving the adhesion, dispersion, and uniformity of the TiO₂/chitosan coating on SiO₂ nanofibers. SiO₂ nanofibers with an initial diameter of 0.79 ± 0.29 μm were coated and hot-pressed, resulting in a final diameter of 1.07 ± 0.57 μm, which corresponds to an approximate increase of 35.4%. In addition, the 1 wt% TiO₂-CTS sample showed the highest adhesion and surface energy, with values of 0.1 nN/nm², indicating the closest intermolecular binding. 3 wt% SiO₂-CTS exhibits a maximum hardness of 5.23 Pa. The 3 wt% TiO₂-chitosan coating demonstrated outstanding mechanical performance, achieving a fracture stress of 0.53 MPa, approximately five times that of the untreated SiO₂ nanofibers, a Young’s modulus of 0.63 MPa, and a toughness to triple of 0.27 MJ/m³—representing substantial improvements over uncoated membranes. Photocatalytic efficiency was significantly enhanced, with grayscale values increasing approximately 36% UV light exposure, indicating the superior degradation of pollutants. Full article

A cost-effective laser marker was employed to fabricate a superhydrophilic, photocatalytic Mg-Ti-based surface on glass under ambient conditions. The photocatalytic layer was first deposited via laser processing, followed by partial laser etching to generate micro/nanostructures on the surface. This method preserves partial photocatalytic functionality while enhancing surface roughness and introducing unique nanostructures, enabling the sample to simultaneously exhibit antifogging, self-cleaning capabilities, and high light transmittance. The optimal sample was achieved by tuning laser processing parameters, including repetition rate and scanning hatch distance. It maintained a water contact angle (WCA) of 0° after 15 days of outdoor exposure, which only increased to 21.2° after 30 days. In comparison, the WCA of reference glass increased from an initial 23.3° to 63.9° over the same period. Furthermore, the amount of dust accumulated on the optimal sample was significantly lower—by up to 43%—than that on the reference glass over one month under both indoor and outdoor conditions. After a single spray cleaning, the dust removal efficiency of the indoor-stored optimal sample reached 70%, which was 56% higher than that of the reference. For samples stored outdoors, a single spray removed 67% of the dust from the optimal surface, compared to only 26% for the reference, highlighting its excellent self-cleaning performance. Additionally, the optimal also showcased remarkable antifogging property, which had been maintained over the one-month exposure period without visible degradation. Moreover, the optimal sample exhibited a 2% enhancement in broadband light transmittance across the 400–1000 nm wavelength range, demonstrating strong potential for photovoltaic applications. The simultaneous achievement of antireflection, antifogging, and self-cleaning performance under both indoor and outdoor conditions over a one-month period has rarely been reported in the literature. Full article

This work presents the design and fabrication of microstructured hydrophobic surfaces via fused filament fabrication (FFF) 3D printing with polylactic acid (PLA). Three geometric patterns—triangular-based prisms (TG), truncated pyramids (TP), and truncated ellipsoidal cones (CET)—were developed to modify the surface wettability. Morphological analysis revealed that the printer resolution limits the accurate reproduction of sharp CAD-defined features. Despite this, TG structures exhibited superhydrophobic behavior evaluated through static water contact angles (WCAs), reaching up to 164° along the structured direction and so representing a 100% increase relative to flat PLA surfaces (WCA = 82°). To improve print fidelity, TP and CET geometries with enlarged features were introduced, resulting in contact angles up to 128°, corresponding to a 56% increase in hydrophobicity. The truncated shapes enable the fabrication of the smallest features achievable via the FFF technique, while maintaining good resolution and obtaining higher contact angles. In addition, surface functionalization with fluoropolymer-coated SiO₂ nanoparticles, confirmed by SEM and Raman spectroscopy, led to a further slight enhancement in wettability up to 18% on the structured surfaces. These findings highlight the potential of FFF-based microstructuring, combined with surface treatments, for tailoring the wetting properties of 3D-printed polymeric parts with promising applications in self-cleaning, de-icing, and anti-wetting surfaces. Full article

Superhydrophobic surfaces, characterized by water contact angles greater than 150°, have attracted widespread interest due to their exceptional water repellency and multifunctional applications. However, traditional fabrication methods often rely on fluorinated compounds and petroleum-based polymers, raising environmental and health concerns. In response to growing environmental and health problems, recent research has increasingly focused on developing green superhydrophobic surfaces, employing eco-friendly materials, energy-efficient processes, and non-toxic modifiers. This review systematically summarizes recent progress in the development of green superhydrophobic materials, focusing on the use of natural substrates such as cellulose, chitosan, starch, lignin, and silk fibroin. Sustainable fabrication techniques, including spray coating, dip coating, sol–gel processing, electrospinning, laser texturing, and self-assembly, are critically discussed with regards to their environmental compatibility, scalability, and integration with biodegradable components. Furthermore, the functional performance of these coatings is explored in diverse application fields, including self-cleaning, oil–water separation, anti-corrosion, anti-icing, food packaging, and biomedical devices. Key challenges such as mechanical durability, substrate adhesion, and large-scale processing are addressed, alongside emerging strategies that combine green chemistry with surface engineering. This review provides a comprehensive perspective on the design and deployment of eco-friendly superhydrophobic surfaces, aiming to accelerate their practical implementation across sustainable technologies. Full article

The vulnerability of copper to corrosion in humid and saline environments remains a critical challenge for its long-term use. In this work, we present a streamlined and scalable approach for fabricating superhydrophobic, corrosion-resistant copper surfaces by integrating a simple wet chemical oxidation process with atmospheric pressure chemical vapor deposition (APCVD) of a perfluorinated silane. The hierarchical CuO nanostructures formed via alkaline oxidation serve as a robust layer, while subsequent silane functionalization imparts low surface energy, resulting in surfaces with water contact angles exceeding 170° and minimal contact angle hysteresis. Comprehensive surface characterization by SEM and roughness analysis confirmed the preservation of hierarchical morphology after coating. Wettability studies reveal a transition from hydrophilic to superhydrophobic behavior, with the Cassie–Baxter regime achieved on nanostructured and silane-functionalized samples, leading to enhanced droplet mobility and self-cleaning effect. Salt spray tests demonstrate that the superhydrophobic surfaces exhibit a corrosion rate reduction of 85.7% (from 2.51 mm/year for bare copper to 0.36 mm/year for the treated surface), indicating a seven-fold improvement in corrosion resistance compared to bare copper. This methodology offers a practical, reproducible route to multifunctional copper surfaces, advancing their potential for use in anti-fouling, self-cleaning, and long-term protective applications. Full article