Photothermal Superhydrophobic Coating Based on Polypyrrole-Modified Boron Nitride with Exceptional Anti-Icing and Deicing Performance

Abstract

The issue of anti-icing and deicing in the low-temperature and high-humidity environment of polar regions has long troubled researchers. The problem cannot be solved perfectly by superhydrophobic coatings alone, and multifunctional composite coatings as well have become a research hotspot. First, hexagonal boron nitride nanosheets were functionalized with polypyrrole (PPy), and then hydrophobic modification was completed by grafting perfluorodecyltriethoxysilane (FAS) to obtain fluorine-modified polypyrrole-functionalized boron nitride (F-BN@PPy). Finally, a photothermal superhydrophobic coating was successfully prepared by using silicone resin as a binder. The coating exhibited excellent photothermal properties, reaching 80 °C in just 3 min under 1 sun irradiation at 25 °C. This can be attributed to the high photothermal conversion efficiency of PPy and the nanostructure of the coating surface, which enhances sunlight utilization. The coating also demonstrated superior hydrophobic properties, reflected by a contact angle of 162° and a sliding angle of 1°, due to the hydrolysis of tetraethyl orthosilicate forming a rough micronanosilica shell and the grafting of the low surface energy FAS. In addition, the performance of the coating maintained good hydrophobic properties by sandpaper abrasion, falling sand impact, bending experiments, or immersion in strong acids and bases for 7 days. This shows that the coating has good mechanical properties and chemical durability. Compared to tinplate, the coating successfully delayed the complete freezing of droplets on its surface at −20 °C by 10 min. On a cooling platform at −40 °C, the F-BN@PPy coating with 1 sun light reached 5.7 °C in only 90 s. The F-BN@PPy photothermal superhydrophobic coating provides an excellent anti-icing/deicing solution for extreme environments.