Design and anti-icing/de-icing performance of photothermally responsive MWCNTs-based hydrophobic coatings

Anti-icing coating technology has broad application prospects in the fields of aircraft wings, power equipment insulators, and highway guardrails due to its efficient and environmentally friendly anti-icing capabilities. In this study, multi-walled carbon nanotubes (MWCNTs) were used as the core photothermal response unit, and their surface activity was enhanced by chemical modification of polydopamine. The micro-nano composite rough structure was constructed by combining SiO₂ modified by PFDTES. The hydrophobic anti-icing coating was prepared by spraying method with epoxy resin (EP) and polydimethylsiloxane (PDMS) as the film-forming matrix. The microstructure and chemical composition of the coating were characterized by SEM and FT-IR. When the mass ratio of PDMS to epoxy resin is 1∶5, the water contact angle of the coating reached 148.7°. The photothermal performance test results show that the temperature can rise to 87℃ under 1.5 suns for 300 s. In addition, the static frosting delay time of the coating is 1489 s, and rapid photothermal defrosting (349 s) is achieved under 1.5 suns. The static icing delay time is 797 s, and the fast photothermal de-icing is realized under 1.5 suns (277 s). The surface decontamination test shows that the coating has excellent self-cleaning performance. The environmental durability of the coating was tested by wear resistance, acid and alkali salt corrosion resistance and water erosion resistance. The results showed that the hydrophobicity retention rate of the coating was more than 90% after 200 times of sandpaper grinding, and the water contact angle decreased by less than 5% after 48 h of acid, alkali and salt immersion.