Li Yin, Mu Hu, Yajie Liu, Yiyi Lin, Yuan Wang, Shaojun Yuan
The development of intelligent, environmentally responsive oil–water separation membranes with reversible wettability presents a promising strategy for controllable emulsion separation and the advanced treatment of complex oily wastewater. Wastewater. In this study, a novel thermally responsive membrane with switchable wettability between superhydrophilic and superhydrophobic states was fabricated via in situ growth of bimetallic metal–organic frameworks (CoZn-ZIF) on electrospun poly(vinylidene fluoride)/poly( N -isopropylacrylamide) (PVDF/PNIPAM) nanofiber membranes. The resulting PVDF/PNIPAM@CoZn-ZIF membrane leverages the thermally induced reversible conformational transition of PNIPAM to exhibit underwater superoleophobicity below its lower critical solution temperature (LCST) and under-oil superhydrophobicity above LCST. This switchable wettability enabled efficient on-demand separation of both oil-in-water (O/W) and water-in-oil (W/O) emulsions, achieving water permeation fluxes exceeding 1900 L·m –2 ·h –1 and oil permeation fluxes over 1150 L·m –2 ·h –1, with separation efficiencies above 99.00% and 99.60%, respectively. Moreover, the embedded Co 1 Zn 3 -ZIF served as a catalyst to activate peroxymonosulfate (PMS), generating reactive oxygen species ( · OH and · SO 4 – ) and enabling rapid degradation of methylene blue, with a removal efficiency of 99.92% within 15 min. This study presents a multifunctional composite membrane as an intelligent, efficient platform for integrated oil–water emulsion separation and organic pollutant remediation.