Electrospun PVDF microfiltration membrane with enhanced piezoelectric demulsification for efficient oil-water separation

Underwater superhydrophilic-oleophobic membranes have been widely regarded as an effective solution for oil-water separation, but their passive antifouling strategies relying on surface modification have long been limited by insufficient interfacial stability and frequent cleaning interruptions during continuous operation. In this study, we developed a piezoelectric composite membrane that integrated demulsification and active antifouling functions. The β -phase content of PVDF nanofibers was regulated by MXene nanosheets, and the highest β -phase content corresponded to the maximum yield of ·OH radicals. Subsequently, FeOOH nanorods were further grown on the fiber surface to construct and stabilize the underwater superhydrophilic-oleophobic interface. During pulsed filtration, piezoelectric activation induced reactive radical generation, which promoted emulsion destabilization and helped mitigate membrane fouling. This design synergistically coupled demulsification with piezoelectric self-cleaning, thereby effectively mitigating irreversible oil fouling. The resulting membrane achieved an oil removal efficiency of 99.5% and maintained a stable permeance of 1057 L·m −2 ·h −1 ·bar −1 during oil-water separation. This work provides a feasible route to mitigate irreversible organic fouling in oil–water separation membranes by integrating demulsification functionality, offering a scalable strategy for the development of piezoelectric active antifouling membranes.