Characterisation of anti-icing CNF/PVDF/PTFE composite coatings on galvanised steel: microstructure, wettability, and wear resistance

Anti-icing superhydrophobic coatings with high durability are crucial for preventing ice accretion on metallic components operating in cold environments. In this work, a robust Carbon nanofiber (CNF)/polyvinylidene fluoride (PVDF)/polytetrafluoroethylene (PTFE) composite coating was fabricated on galvanised steel using a simple wet-chemical route and air-spray deposition. The resulting hierarchical micro/nanostructured surface exhibited superhydrophobic behaviour with a static water contact angle of 167.3 ± 1.2°. Water droplets exhibited visible mobility on the coated surface, qualitatively indicating low water adhesion. Microscopic and spectroscopic analyses revealed a well-interconnected CNF network strongly bound to the PVDF/PTFE matrix, which enhanced surface roughness, interfacial adhesion and mechanical integrity. The composite exhibited enhanced thermal stability and showed significantly delayed icing compared to CNF/PVDF and CNF/PTFE reference coatings. Wear tests further demonstrated superior durability, with the PTFE-assisted friction stabilisation that sustained low adhesion and friction during sliding. These results indicate that the CNF/PVDF/PTFE composite coating combines outstanding superhydrophobicity, anti-icing efficiency, thermal stability and wear resistance, making it a promising candidate for long-term anti-icing protection of galvanised steel structures in transportation and energy systems.