Fully Sustainable, Nanoparticle-Free, Fluorine-Free, and Robust Superhydrophobic Cotton Fabric Fabricated via an Eco-Friendly Method for Efficient Oil/Water Separation

Traditional superhydrophobic materials for oil/water separation not only depend on nonrenewable feedstocks but also lead to secondary environmental pollutions after discarding, due to the presence of inorganic nanoparticles and toxic fluorine-containing chemicals. Herein, we report a fully sustainable, nanoparticle-free, and fluorine-free superhydrophobic cotton fabric (CF) fabricated via an eco-friendly method, that is, roughness creation by enzyme etching followed by surface coating with an epoxidized soybean oil thermoset and subsequent low surface energy modification with stearic acid. The superhydrophobic CF exhibited excellent durability with surface superhydrophobicity surviving from mechanical abrasion, tape peeling, ultrasonication, chemical resistance, and low/high temperature treatment, due to the enzyme etching-induced stable surface structure with covalently linked low-energy substance. The superhydrophobic CF showed excellent oil/water separation performance with a high separation efficiency and high oil flux. With outstanding mechanical robustness, chemical and environmental resistances, and excellent oil/water separation performance, the fully sustainable superhydrophobic CF can be applied as an environmentally friendly substitute to nonrenewable and harmful chemicals containing oil/water separation materials.