Fluorine-Free Diatomite-Based Composite Multifunctional Anti/Deicing Coatings via Molecular Structure Synergistic Regulation

Ice formation poses a severe threat to the infrastructure safety and operational reliability. However, anti-icing materials such as superhydrophobic surfaces and slippery liquid-infused porous surfaces (SLIPS) meet challenges including performance degradation, lubricant loss, and complex preparation processes. This study presents a strategy for fabricating fluorine-free multifunctional composite anti-icing coatings through synergistic molecular interaction-structure regulation. The coatings first utilize porous diatomite as the oil storage carrier, epoxy resin as the matrix, silicone oil as the lubricant, and carbon nanotubes as the photothermal component and are prepared via a scalable room-temperature spraying process. During the curing process, diatomite and epoxy resin form a hierarchical micronano rough structure in situ at the interface through physical adsorption and chemical anchoring, while the three-dimensional cross-linked network ensures stable adhesion. It can stably load silicone oil, addressing the challenge of lubricant loss in conventional SLIPS. The coating exhibits a contact angle of 109.2° and a sliding angle of merely 7° and can elevate the surface temperature by over 30 °C within 200 s above ambient temperature under 1.0 sun. The synergistic photothermal and slippery effects enable efficient active-passive anti-icing. At -25 °C, preformed ice layers and thick frost melt within 140 and 220 s, respectively. Consequently, the coating exhibits hydrophobicity, antiadhesion, self-cleaning, and photothermal anti-icing performance, while demonstrating mechanical durability. This provides an efficient and practical solution for industrial sectors requiring anti-icing.