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Icing/frosting poses a significant problem for materials used in everyday applications. In recent years, anti-icing methods utilizing superhydrophobic materials have become popular. These materials have superhydrophobic surfaces with air-solid composite structures, which can prevent icing/frosting by creating air cushions in the micro- and nano-scales of the rough structure. However, long-term protection of the substrate is challenging due to air leakage from the air cushion and the breakdown of the superhydrophobic coating. The use of superhydrophobic materials in cold environments is also greatly limited by this shortcoming. In this paper, superhydrophobic copper foam (SHS CF) was created by using electrochemical oxidation and impregnation techniques and subsequent modified by fluorosilane coupling agent on the copper foam surface to reduce surface particle activity through condensation reactions, achieving a superhydrophobicity with a water contact angle of up to 170±2°. Furthermore, gas was utilized to form a specific rough structure by combining with Cu(OH) 2 micro-nanopins, leading to the development of long-lasting gas in SHS CF (LAG-SHS CF). The LAG-SHS CF exhibited impressive anti-frost characteristics, with a delayed icing time of approximately 2171 s. Notably, the SHS CF retained strong wetting capabilities and excellent resistance to abrasion, UV, acid, and alkali even after the removal of LAG, which was ascribed to the fact that the composite structure effectively reduces the solid-liquid contact area and has a high roughness. These properties provide a solid foundation for the application of LAG-SHS CF. The findings of this study contribute to the creation of new materials with anti-icing and anti-frost properties. [Display omitted] [ABSTRACT FROM AUTHOR]

Because 304 stainless steel is extensively used in everyday life, surface icing frost would cause annoyance; thus, the research on 304 stainless steel with frost inhibition is quite important. The superhydrophobic surface anti-frost is energy-saving and ecologically beneficial, but it also avoids typical defrosting, which reduces energy consumption, pollution, and other difficulties. As a result, the investigation of superhydrophobic surface frost inhibition performance offers promising practical potential. However, traditional manufacturing procedures for superhydrophobic surfaces have proven to be difficult and expensive, rendering them unsuitable for mass production. In this paper, a simple hydrothermal and sol-gel method were used to prepare the superhydrophobic surface wettability of 304 stainless steel and determine the frosting behavior of superhydrophobic ZnO, hydrophobic ZnO, hydrophilic ZnO, and 304 stainless steel sheets at low ambient temperatures. The frost resistance of superhydrophobic ZnO was studied. As a result, this study provides a novel idea for rationally designing frost-resistant superhydrophobic surfaces at low ambient temperatures. [Display omitted] • The superhydrophobic surface was prepared by sol-gel and chemical deposition method. • This sample shows physical/chemical/mechanical stability in harsh environments. • This sample shows excellent superhydrophobicity and anti- frosting properties. [ABSTRACT FROM AUTHOR]

Artificial superhydrophobic coatings with mechanical stability, chemical stability, and physical stability have been achieved separately. However, achieving these properties at the same time is still a challenge. In this paper, a novel combination of sintering and spraying strategy was proposed to design a 509 reagent (1, 1, 2, 3, 3, 3-hexafluoro-2-(trifluoromethyl)propane-1-sulfonate)@Cu nanoparticles/Cu mesh/Cu organic-inorganic multilayer superhydrophobic coating. Surprisingly, the superweting coatings exhibit strong mechanical robustness undergoing cyclic tape peeling, sand/sandpaper abrasion and ultrasonic treatment. At the same time, the superhydrophobic coatings are also exposed to high temperature, UV irradiation and boiling water treatment to test its chemical stability. Moreover, the superhydrophobic coatings demonstrate outstanding physical robustness undergoing tensile force due to the combination of 509 reagent, Cu nanoparticles and Cu mesh. With multifaceted robustness, this superhydrophobic multilayer coating could be used in high-tech equipment area (such as: wear-resistance moving machine components, microfluidic devices, fluid microchips, microreactors, and so on) with strong alternating or impact loads, high friction service, and chemical corrosion. [Display omitted] • A novel combination of sintering and spraying strategy was proposed to design a multifunction superhydrophobic coatings. • These coatings can achieve mechanical/chemical/physical robustness simultaneously. • The coatings could be used in high-tech equipment field with severe environment. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces have many advantages in wetting fields. However, the lack of easyily production methods and limited mechanical/chemical/physical robustness remain the two most pertinent barriers to the scalability, large-area production, and widespread use of superhydrophobic materials. In this work, a mechanical/chemical/physical robustness superhydrophobic coating sample consisting of a regular array of square Cu mesh with secondary nano structures of polytetrafluoroethylene (PTFE) and SiO 2 powders on the sidewalls is produced through a scalable and easyily production technique of the combination of hot-press sintering and subsquent spray-coating. The Cu mesh is used as a template to fabricate the grooves and bulges as the first-level roughness, and the SiO 2 powder is maintained on the surface of the coatings to form two-level hierarchical structures, with both micro and nano structures firmly affixed by low-surface energy polymer binder (PTFE). For comparison, Cu mesh and Cu mesh/Cu sample are also produced. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and time-dependent apparent contact angle are used to examine the as-prepared materials. The corrosive solution, high temperature, UV irradiation, ultrasonic treatment, water drop hitting, sand drop impacting, multi-cycled sandpaper abrasion, tape-peeling test, and self-cleaning test was conducted to simulate the real-world damages. All of the armored superhydrophobic coating samples have an apparent water contact angle of more than 150°, as well as outstanding mechanical and chemical resilience. The salt spray test and mechanical behavior of the as-prepared samples revealed that the armored superhydrophobic coating sample has the lowest corrosion rate, the highest tensile strength, and the greatest elongation among these threee as-prepared samples, implying that it has the best anti-corrosion ability and mechanical property. This strategy might give guidance for the development of composite materials that need to retain mechanical/chemical/physical robustness in severe working conditions. [Display omitted] [ABSTRACT FROM AUTHOR]