Robust and durable superhydrophobic steel and copper meshes for separation of oil-water emulsions

Global growing challenges of water pollution due to oil spills bring a desperate need of efficient solution for oil-water separation. The development of superhydrophobic metallic mesh brings hope to resolving this serious problem. A strategy is proposed to fabricate superhydrophobic metallic meshes, those can separate oil-water mixtures and oil-water emulsions efficiently. After surface modification with perfluorodecyltriethoxysilane (PFDTS) and TiO2 nanoparticles, obtained steel and coper meshes exhibit excellent superhydrophobicity. Additionally, superhydrophobic metallic meshes are found to be stable in harsh environmental conditions such as corrosive chemical, high temperature and mechanical disturbances. Bouncing, pinning, and splashing of water droplets on coated mesh are observed at different impact conditions. Coated meshes show the excellent self-cleaning property. Prepared superhydrophobic meshes are found to be exceptionally efficient on oil-water emulsion separation. In addition, the coated meshes show high separation efficiency for a series of oil-water mixtures. Moreover, the coated meshes still maintain high separation efficiency after multiple separation cycles for the oil-water mixture. This work can be helpful for developing a facile, inexpensive and environmentally friendly superhydrophobic metallic mesh in worldwide application of oil-water separation.