Biomimetic fabrication of micron/nano-meter assembled superhydrophobic polymer fiber fabrics for oil/water separation

Inspired by the lotus leaf effect and strong adhesion ability of mussel adhesive protein in nature, highly efficient superhydrophobic polymer fiber fabrics were fabricated using a novel, facile and bottom-up assembly strategy that introduced SiO2/polydopamine/Ag nanoparticles/1H,1H,2H,2H-perfluorodecanethiol to three-dimensionally construct micro-nano hierarchical rough structures on the fabric surfaces with low surface energy. Results showed that the hierarchical substrate-core-shell-satellite architecture structure with three-tier distribution in the as-fabricated fabrics was successfully achieved. The obtained fabrics displayed water contact angles in the range from 147.8°±2.5° to 160.1°±2.8° with SiO2 particles of different sizes (0.2–0.4 μm). Moreover, the as-fabricated fabrics could effectively separate a variety of oil/water mixtures with high separation efficiencies beyond 90% and maintain good superhydrophobicity for 20 cycles. In addition, the mechanism for oil/water mixture separation was also discussed. Therefore, such superhydrophobic polymer fiber fabrics were promising in designing smart surfaces in, for example, oil/water separation, smart oil engineering (the conductivity of Ag nanoparticles on fabric surfaces), microfluidic devices, etc.