Dual-bioinspired fabrication of Janus Micro/nano PDA-PTFE/TiO2 membrane for efficient oil-water separation

Oily wastewater poses a severe threat to the environment and human health, and its disposition is a worldwide urgency. Rencently, Janus membranes has provided excellent selectivity for oil/water separation due to thin layers of different wettability on opposite sides. However, the fabrication of Janus asymmetric multilayer with simple syntheses and excellent stability has been proved challenging. Herein, a Janus polydopamine-polytetrafluoroethylene/titanium dioxide (PDA-PTFE/TiO2) membranes were inspired by dual-bionic strategy (lotus leaf and mussel) and constructed by centrifugal spinning technology. The membranes showed significant separation efficiency for both water–oil mixtures and emulsions above 99%. Most notably, the separation efficiency of the membranes are still maintained above 98.5% after 24 h immersion in the corrosive solutio. Meanwhile, the nanofiber membrane has outstanding reusability, acid/alkali resistance, and mechanical stability. Therefore, the dual-bioinspired Janus micro/nano PTFE/TiO2 membrane suggests a promising potential application for a sustainable and effective oil–water separation membrane in the future.