Smart Nylon Membranes with pH-Responsive Wettability: High-Efficiency Separation on Demand for Various Oil/Water Mixtures and Surfactant-Stabilized Emulsions

Water contaminated with various oils has become one of the most pervasive environmental issues. Developing an efficient and durable separation membrane is of significance but challenging due to the critical limitations of nonuniversality and discontinuity for oil/water separation. Herein, a material is presented by combining the porous nylon membrane with self-assembled thiol molecules, exhibiting tunable wettability property upon the pH variation. Such a smart membrane shows high hydrophobicity in nonbasic environment while transition into superhydrophilicity under basic condition, demonstrating a robust and controllable separation performance for various oil/water mixtures and surfactant-stabilized emulsions along with excellent recyclability of the long-term separation. This facile and general strategy suggests encouraging the development of the next generation of energy-saving water treatment systems, applying to intelligent separation and on-demand oil-spills cleanup.