Fabrication of antibacterial and self-cleaning CuxP@g-C3N4/PVDF-CTFE mixed matrix membranes with enhanced properties for efficient ultrafiltration

Despite membrane separation technology has been extensively implemented in various field, the fouling caused by bacterial and organic dye seriously impair the performance and lifespan of the membrane, the anti-fouling modification of the membrane is still a challenging. In this work, the antibacterial and self-cleaning poly (vinylidene fluoride-chlorotrifluoroethylene) (PVDF-CTFE) mixed matrix membranes were prepared by non-solvent induced phase separation method using self-made graphite carbon nitride nanosheet wrapped copper phosphide (CuxP@g-C3N4) as modification additive. The sequel of the incorporated CuxP@g-C3N4 nanosheet content on the morphology, pore structure and physicochemical structure of membranes was investigated in terms of pure water flux, anti-fouling and antibacterial properties. The results showed that the addition of CuxP@g-C3N4 nanosheets not only improved the hydrophilicity and mechanical property of the membranes, but also enabled PVDF-CTFE membrane with the ability of inactivation bacteria and self-cleaning, which significantly enhanced the anti-fouling performance of PVDF-CTFE membrane in complex environment. When the amount of CuxP@g-C3N4 reached 2 wt%, the mixed matrix membrane possessed outstanding comprehensive performance with the pure water flux of 641.1 L m−2 h−1, antibacterial rate over 99% and self-cleaning under simulated sunlight, making the mixed matrix membrane a potential choice for wastewater treatment. In conclusion, this study enlightened the fabrication strategy of multifunctional mixed matrix membranes. [Display omitted] •CuxP@g-C3N4 was used as a catalytic additive to prepare PVDF-CTFE mixed matrix membrane.•Introduction of CuxP@g-C3N4 enhanced the membrane permeability and mechanical property.•Mixed matrix membrane exhibited excellent antibacterial and self-cleaning performance.