Superhydrophobic Anti-Corrosion Coatings for Metal Surfaces: A Systematic Review from Fabrication to Performance

Freezing delay of water droplets on metallic hydrophobic surfaces in a cold environment

Mimicking natural superhydrophobic surfaces and grasping the wetting process: A review on recent progress in preparing superhydrophobic surfaces

A superhydrophobic surface featuring high roughness and low surface energy is designed for effective corrosion protection on aluminum via a facile and cost-effective electrochemical route. The effects of the electrolyte composition and electrodeposition time on the surface wettability were investigated. Moreover, the corrosion resistance performance of the as-prepared superhydrophobic aluminum surface was studied using electrochemical impedance spectroscopy and electrochemical noise techniques. The results show that the superhydrophobic aluminum surface obtained at 2 V for 20 min has a high static water contact angle of 155.8°. Both the average corrosion rate and pitting intensity are remarkably inhibited by the as-prepared superhydrophobic surface on aluminum. Moreover, the static water contact angle for the obtained superhydrophobic surface remains above 150° after exposure to 3.5 wt% NaCl solution for 30 days. This facile and economical superhydrophobic surface, with its excellent anti-corrosion property and stability, shows significant potential for use in industrial applications.

Trends of Impact Ice Adhesion on Various Surfaces

An outlook on tunable superhydrophobic nanostructural surfaces and their possible impact on ice mitigation

Toward Passive Defrosting with Heterogeneous Coatings

Superhydrophobic brass surfaces with tunable water adhesion fabricated by laser texturing followed by heat treatment and their anti-corrosion ability

Engineering of superhydrophobic silica microparticles and thin coatings on polymeric films by ultrasound irradiation

Interfacial Effects of Superhydrophobic Plant Surfaces: A Review

Preparation of self-healing superhydrophobic polyacrylate coatings based on silica matrix-microcapsules containing corrosion inhibitor for long-term corrosion protection

Glutenin phase transition as a method of fabricating primer for superhydrophobic and corrosion-resistant coating

Superhydrophobic surfaces have been intensively investigated in recent years. However, their durability remains a major challenge before superhydrophobic surfaces can be employed in practice. Although various works have focused on overcoming this bottleneck, no single surface has ever been able to achieve the comprehensive durability (including tangential abrasion durability, dynamic impact durability and adhesive durability) required by stringent industrial requirements. Within the hierarchical structures developed for superhydrophobicity in typical plants or animals by natural evolution, microstructures usually provide mechanical stability, strength and flexibility to protect functional nanostructures to enable high durability. However, this mechanism for achieving high durability is rarely studied or reported. We employed an ultrafast laser to fabricate micro/nanohierarchical structures on metal surfaces with tunable micro-cones and produced abundant nanostructures. We then systematically investigated their comprehensive mechanical durability by fully utilizing the protective effect of the microstructures on the functional nanostructures via the tunable design of micro-cones. We confirm that the height and spatial period of the microstructures were crucial for the tangential abrasion durability and dynamic impact durability, respectively. We finally fabricated optimized superhydrophobic tungsten hierarchical surfaces, which could withstand 70 abrasion cycles, 28 min of solid particle impact or 500 tape peeling cycles to retain contact angles of greater than 150° and sliding angles of less than 20°, which demonstrated exceptional comprehensive durability. The comprehensive durability, in particular the dynamic impact durability and adhesive durability, are among the best published results. This research clarifies the mechanism whereby the microstructures effectively protected the functional nanostructures to achieve high durability of the superhydrophobic surfaces and is promising for improving the durability of superhydrophobic surfaces and thus for practical applications.

Super-hydrophobic (SH) surfaces mostly motivated by the primordial surface designs considerably increase the life of the substrate. In the present work, effort has been made towards rational development of the SH surface on ASTM A479 steels substrates coated with WC–10Co–4Cr using high-velocity oxy-fuel. Distinct coating configurations have been investigated to analyse the effect of circular texturing patterns using nanosecond laser fibre texturing machine for the development of SH surfaces. Here, a freshly prepared solution of Hexafor 644-D/PFOA/Al2O3 nanoparticles was utilized for simple HVLP spraying and dip coating methods to formulate SH coatings on untextured and textured surfaces. The developed SH surfaces were characterized by field emission scanning electron microscope, X-ray diffraction, energy-dispersive spectroscopy and surface roughness tester. Water repellency of fabricated SH surfaces and its durability were studied by measuring the water contact angle (WCA), sliding angle, sandpaper abrasion test, tape peeling tests and water impact tests. All the configurations of the developed SH surfaces were found to be sustainable against the different wear tests performed during the study and exhibited excellent repellence to water and ink droplets. The highest WCA and sliding angle for textured and dip-coated SH surface (configuration—C 2.1) were found to be 162.6° and 10°, respectively. Further, it was found that during the sandpaper abrasion test, and the configuration corresponding to textured surfaces after thermal spray coating sustained super-hydrophobicity up to 30 cycles. Because of simple steps and the desired properties obtained by proposed methods, the coatings may be used for producing SH surfaces in apt industrial applications.

Superhydrophobic materials are found in a suite of scientific and industrial applications, and given their broad potential use, there is great interest in facilitating their mass production. Although numerous methods have been used to produce superhydrophobic materials, only a few are capable of fabricating superhydrophobic surfaces and materials at an industrial scale. Techniques such as injection molding, compression molding, hot embossing, and polymer casting play an important role in the mass production of superhydrophobic polymer surfaces. This technical literature review summarizes recent advances in the polymer molding processes used to fabricate superhydrophobic materials. Here, we review replication methods and the materials that can be used by these approaches. We also evaluate the advantages and disadvantages of these methods and discuss the challenges of molding and demolding single-level structures (e.g., microstructures and nanostructures) and multilevel structures (e.g., micro-nanostructures, micro-microstructures, and micromicro-nanostructures), with a focus on superhydrophobic surfaces. We evaluate the relationship between structure geometry and the wettability of a surface, highlighting the effect of structure type and size in achieving the desired wettability. We then offer perspectives, discuss current limitations, and suggest required studies. This review aims to assist researchers in understanding the fundamentals related to the fabrication of patterned surfaces via polymer molding processes and offer avenues for the successful creation of superhydrophobic polymeric surfaces.

Artificial superhydrophobic surfaces hold significant potential in various domains, encompassing self-cleaning, droplet manipulation, microfluidics, and thermal management. Consequently, there is a burgeoning demand for cost-effective, mass-producible, and easily fabricated superhydrophobic surfaces for commercial and industrial applications. This research introduces an efficient, uncomplicated method for constructing hierarchical structures on hard substrates such as binderless tungsten carbide (WC) and glass substrates. The WC substrates were processed by using electrical discharge machining (EDM) with a magnetic-assisted self-assembly sheet electrode. The resultant surfaces comprised micropillars/microgrooves and diminutive craters formed by discharge and ablation, respectively. These surfaces exhibited superior hydrophobic properties, which can be attributed to the modified surface energy and surface texture construction. Our study indicates that a superhydrophobic surface can be achieved on a textured binderless WC. The maximum contact angle and minimum roll-off angle of the hierarchical structure induced by EDM with a magnetic-assisted self-assembly sheet electrode are about 158 and 5°, respectively. The advancing and receding angles are about 161° ± 2 and 157° ± 3, respectively, when the base is tilted at 3°. Furthermore, we have successfully replicated this superhydrophobic structured surface on glass substrates utilizing glass molding technology. This innovative approach to creating superhydrophobic surfaces on hard materials paves the way for the mass production of functional structures on other materials, such as metallic glass, titanium alloy, and mold steel. Most crucially, the proposed fabrication technique offers a straightforward, cost-effective route for creating functional surfaces, rendering it attractive for large-scale industrial production due to its considerable application prospects.