In situ oxidized TiO2/MXene ultrafiltration membrane with photocatalytic self-cleaning and antibacterial properties

RSC Adv. 2023 May 25;13(23):15843-15855. doi: 10.1039/d3ra02230g. eCollection 2023 May 22.

Abstract

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-TiO2 MXene lamellar materials were synthesized and then 2D membranes were fabricated using vacuum filtration. The presence of nano TiO2 particles as an interlayer support layer widened the interlayer channels, and also improved the membrane permeability. The TiO2/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 TiO2/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 TiO2/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 TiO2/MXene membranes demonstrated over 95% resistance against E. coli. And the XDLVO theory also showed that the loading of TiO2/MXene slowed down the fouling of the membrane surface by protein-based contaminants.