In situ oxidized TiO 2 /MXene ultrafiltration membrane with photocatalytic self-cleaning and antibacterial properties.

Self-cleaning, antimicrobial ultrafiltration membranes are urgently needed to alleviate the low flux problems caused by membrane fouling in water treatment processes. In this study, in situ generated nano-TiO 2 MXene lamellar materials were synthesized and then 2D membranes were fabricated using vacuum filtration. The presence of nano TiO 2 particles as an interlayer support layer widened the interlayer channels, and also improved the membrane permeability. The TiO 2 /MXene composite on the surface also showed an excellent photocatalytic property, resulting in enhanced self-cleaning properties and improved long-term membrane operational stability. The best overall performance of the TiO 2 /MXene membrane at 0.24 mg cm -2 loading was optimal, with 87.9% retention and 211.5 L m -2 h -1 bar -1 flux at a filtration of 1.0 g L -1 bovine serum albumin solution. Noticeably, the TiO 2 /MXene membranes showed a very high flux recovery under UV irradiation with a flux recovery ratio (FRR) of 80% as compared to the non-photocatalytic MXene membranes. Moreover, the TiO 2 /MXene membranes demonstrated over 95% resistance against E. coli . And the XDLVO theory also showed that the loading of TiO 2 /MXene slowed down the fouling of the membrane surface by protein-based contaminants.