Oil-Water Separation Using a Self-Cleaning Underwater Superoleophobic Micro/Nanowire Hierarchical Nanostructured Membrane

Abstract

In this study, we fabricated a novel micro/nanowire hierarchical membrane with flexible, self-cleaning and underwater superoleophobic properties for efficient oil-water separation under vacuum filtration. This novel membrane composed of ultralong copper microwires (MW) and functional TiO2 nanowires (NW). The ultralong copper microwires act as a scaffold, as well as providing mechanical flexibility for the membrane, which allow it to be operated under vacuum-driven condition. Meanwhile, underwater superoleophobic TiO2 nanowires membrane provides nano- scale pore size, ensuring the filtration of smaller oil droplets under vacuum condition. Moreover, the possession of the self-cleaning function of TiO2 nanowires allows the degradation of foulants and contaminants under UV irradiation, which promote the facile recovery of the used membrane. Clearly, the employment of this novel membrane can be considered as a practical option for efficient oil-water separations.