Durable superhydrophobic cotton filter prepared at low temperature for highly efficient hexane and water separation

Abstract

Abstract A composite of ZnO and cotton fabric (ZnO CF) with a superhydrophobic surface was successfully synthesized with Teflon-lined stainless steel autoclave at low temperature 100 °C. X-ray diffraction (XRD) results indicated that the fabricated ZnO CF had a uniform stacked hexagonal slice structure without any impurities. The fabric surface firmly bonded with ZnO through chemical bonding and possessed superhydrophobicity with a surface water contact angle (WCA) greater than 150°. The rough structure of ZnO and the enhancement of nonpolar functional groups on the composite surface gave ZnO CF its superhydrophobicity. ZnO CF showed a stable and robust self-cleaning property. When applied to separate a mixture of water (dyed with methylene orange) and organic solvent (hexane), ZnO CF achieved a separation efficiency of over 99% that decreased only insignificantly even after several cycles. Therefore, this outstanding separation performance demonstrates the strong potential of ZnO CF for practical applications such as wastewater treatment and water purification.