Cu-based MOFs@TiO2/PVDF composite membrane for efficient oil-water separation and bacterial isolation and sterilization

Developing a multifunctional composite membrane with efficient oil-water separation, antifouling, stability, bacterial filtration, and antibacterial functions is essential for treating oily and organic medical wastewater. In this study, a PVDF/TA/APTES/CMCS/Cu-BTC@TiO 2 membrane was fabricated using mussel-inspired surface chemistry and dip-coating. Hydrophilic tannic acid (TA) and carboxymethyl chitosan (CMCS) enhanced membrane hydrophilicity, while hydrolyzed γ-aminopropyl triethoxysilane (APTES) formed a thin SiO 2 network layer that improved the stability of the deposited coating. Photocatalytic TiO 2 and biocompatible Cu-BTC contributed to the membrane’s photothermal response, antibacterial activity, and bacterial filtration. The membrane exhibited superhydrophilicity (water contact angle 10.3°), underwater oleophobicity (oil contact angle 153.9°), high water flux (5963.33 L·m −2 ·h −1 ), and 98.85% separation efficiency. It also achieved 99.99% bacterial filtration efficiency, 99.9% photothermal antibacterial rate, 99.99% photocatalytic sterilization, and self-cleaning ability. This multifunctional membrane shows great promise for oil-water separation and medical wastewater treatment.