A facile approach to fabricating fluorine-free superhydrophobic cotton fabric with excellent oil-water separation performance

With the increasing deterioration of environmental and ecology caused by industrial wastewater pollution and petroleum spill accidents, superhydrophobic materials for oil-water separation have attracted considerable attention. Herein, we propose a facile approach to fabricate fluorine-free superhydrophobic cotton fabric (CF) for oil-water separation after the coverage of chitosan (CS) and titanium dioxide (TiO2) nanoparticles and the subsequent hydrophobization modification by hexadecyltrimethoxysilane (HDTMS). The obtained HDTMS-TiO2/CS@CF showed superhydrophobicity with a high water contact angle of 160.6 degrees as well as excellent self-cleaning capability, non-adhesion capability and surface stability. Moreover, the CF was successfully applied for the separation of various oil-water mixtures. The separation efficiency for trichloromethane-water mixture reached 95.8%, and still maintained 95.6% after 30 separation cycles. In addition, the CF also possessed superior photocatalytic degradation capability for organic contaminant such as oil red O and the degradation rate was 86.2% under UV irradiation for 180 min. The preparation method in this work is simple, environmentally friendly, low-cost, and easy to produce on a large scale. The findings conceivably stand out as a new method to fabricate superhydrophobic materials and show great application potential in the fields of oil-water separation and water purification.