Lotus-leaf-mimetic catalytic cleaning membranes with enriched oxygen vacancies for efficient water purification

Separation membranes with inherent low-carbon properties are crucial for energy‒water sustainability but suffer from fouling issue and performance deficiency. Herein, a lotus-leaf-mimetic catalytic membrane is synthesized via 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP)-Co metal-organic intermediate layer-mediated MnO₂ mineralization, transforming hydrophobic polymeric membranes into unique self-cleaning membranes. The derivative abundant oxygen vacancies during hetero-phase mineralization boost their catalytic capability. The lotus leaf-mimicking nano/micro-water pockets at the interface enable the membrane operando flux recovery to reach 99.9%. Most interestingly, the membrane exhibited 24.8-fold greater antifouling ability and 10.6-fold greater recovery compared with the unmineralized membrane, significantly outperforming state-of-the-art membranes. The exceptional performance for water treatment is attributed to active catalytic antifouling coupled with hierarchical antifouling barriers. The computational simulations reveal electron-rich bell-like structures with electron-deficient metal cores. This work paves a way for the fabrication of biomimetic materials for efficient water treatment and beyond. This study reported a lotus-leaf-inspired surface engineering to fabricate a superhydrophilic self-cleaning catalytic membrane via hexahydroxytriphenylene-Co metal-organic framework/film-mediated hierarchical raspberry-like MnO₂ mineralization.