Intelligent Bionic Design of Robust Superamphiphobic Fire Sensing EP/F-POS@Fe₃O₄ Coating on Wood Substrate

Wood is a widely used carbon-storing material, but its applications are constrained by vulnerabilities to water, oil and fire. Existing coatings have limited functionalities, failing to meet the intelligent requirements of modern wood products and constructions. Inspired by bionics, a robust superamphiphobic fire sensing EP/F-POS@Fe₃O₄ coating was designed on wood substrate, fabricated from functional ferroferric oxide (Fe₃O₄) particles, tetraethyl orthosilicate (TEOS, hydrolyzed into polysiloxane), 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PFDTMS), and epoxy resin (EP) adhesive. Optimizing the EP content not only enhances coating stability but also engineers surface micronano reentrant structures, endowing the wood with excellent superamphiphobicity (water/oil contact angles >150°). The EP/F-POS@Fe₃O₄ coating maintains robust hydrophobic and oleophobic properties under sandpaper abrasion, tape peeling, glass bead impact, and knife scratching tests. At the same time, the coating's effectiveness in reducing the wood's liquid absorption further confirms its stable water/oil repellency. Importantly, beyond passive flame retardancy, the EP/F-POS@Fe₃O₄ coating features a breakthrough active fire alarm function: nonconductive under ambient conditions, it acts as a sensor upon flame exposure, exhibiting ultrafast (∼3 s) intelligent visual alarm response and excellent repeatability (>10 cycles), holding potential to mitigate fire risks. Obviously, the EP/F-POS@Fe₃O₄ coating shows great promise for future applications in wooden architecture and smart furniture.