Fluorine-Free Photothermal Superhydrophobic Copper Oxide Micro-/Nanostructured Coatings for Anti-icing/De-icing Applications

Excessive ice accumulation in low-temperature environments can lead to serious economic losses and unexpected safety hazards. Therefore, effective measures must be developed to impede icing and to quickly de-ice. Superhydrophobic coatings with low surface energy and rough structure can effectively retard ice formation. However, in low temperature and high humidity environments, superhydrophobic coatings may form interlocking structures with ice, which increases the adhesion strength of ice to the coating and makes it difficult to remove ice. Photothermal coatings utilize the photothermal effect of photothermal materials to achieve effective photothermal conversion for photothermal de-icing. So photothermal de-icing is a good solution to the drawbacks of superhydrophobic anti-icing. At the same time, fluorine-containing materials used to prepare superhydrophobic surfaces are potentially hazardous to humans and the environment. Therefore, we show a method to achieve a combination of photothermal de-icing and superhydrophobic anti-icing to obtain a fluorine-free photothermal superhydrophobic coating (PSC). The substrate surface is electrolessly plated with copper and then etched to obtain the superhydrophobic structure with photothermal effect. Under simulated irradiation conditions, the PSC reached a surface temperature of 82.0 °C in 10 min and exhibited an extremely short photothermal de-icing time, about one-third that of the substrate. In addition, the self-cleaning, antifouling, and alkali resistance of PSC could help the coating in long-term outdoor applications. The robust copper oxide (CuO) micro-/nanostructures allow the PSC to maintain significant photothermal and hydrophobic properties after friction and water impact, contributing to improving environmental resilience. The synergy effect of superhydrophobicity and photothermal properties greatly improves anti-/de-icing performance, providing a more convenient and environmentally friendly approach for the design of anti-/de-icing coatings.