A four-tier hierarchical architecture for superamphiphobic and flame-retardant fabrics with enhanced self-buoyancy and anti-icing properties

Environmentally robust super-repellent and flame-retardant materials satisfying various functional necessities under harsh weather events to provide protections from fouling and burn injuries have proven challenging to attain. Here, a unique four-tier hierarchical macro/micro/nanostructure is designed and constructed by regulating the accretion of multiscale organic–inorganic hybrid building blocks using silica nanoparticles, microsized ammonium polyphosphate, fluorinated alkyl silane and fluorocarbon surfactants, leading to appreciable self-cleaning, antifouling and anti-icing properties in addition to excellent flame retardancy. The fabricated rough surface exhibits super-repellency to a variety of liquids, including synthetic blood, edible oil, hexadecane, concentrated H2SO4, and even dodecane. The hierarchy of the surface texture is found to be decisive for satisfactory liquid repellency and weather resistance. In addition, the coated fabric presents an enhanced buoyancy which could load 40.2 times its own weight in water and demonstrates a favorable icing delay time of 1168 s. Various stability tests show that the coating maintains a good nonwetting state even under harsh conditions, including mechanical abrasions, repeated washing, chemical corrosion, heat treatment, and strong ultraviolet irradiation. Thus, this work provides a feasible and sustainable strategy for constructing multifunctional protective materials used in advanced protective clothing, infrastructure and transportation facilities.