Conductive MXene ultrafiltration membrane for improved antifouling ability and water quality under electrochemical assistance

Abstract

Membrane fouling is a major challenge for the membrane separation technique in water treatment. Herein, an MXene ultrafiltration membrane with good electroconductivity and hydrophilicity was prepared and showed excellent fouling resistance under electrochemical assistance. The fluxes under negative potential were 3.4, 2.6 and 2.4 times higher than those without external voltage during treatment of raw water containing bacteria, natural organic matter (NOM), and coexisting bacteria and NOM, respectively. During the treatment of actual surface water with 2.0 V external voltage, the membrane flux was 1.6 times higher than that without external voltage and the TOC removal was improved from 60.7% to 71.2%. The improvement is mainly attributed to the enhanced electrostatic repulsion. The MXene membrane presents good regeneration ability after backwashing under electrochemical assistance with the TOC removal remaining stable at around 70.7%. This work demonstrates that the MXene ultrafiltration membrane under electrochemical assistance possesses excellent antifouling ability and has great potential in advanced water treatment.