MXene-PANI/PES composite ultrafiltration membranes with conductive properties for anti-fouling and dye removal

Abstract

The appearance of the composite membrane provides a new research direction for reducing membrane fouling. In this study, polyaniline (PANI) and Ti3C2Tx (MXene) were combined by the electrostatic assembly method where PANI was used to adjust the distance between MXene layers and construct the conductive network. The conducting mixed ultrafiltration membranes were prepared by the non-solvent induced phase separation method, in which MXene and PANI were mixed into a polyethersulfone (PES) matrix. The permeation flux of pure water of the MXene-PANI/PES membrane was increased by 200.9%, the retention rate of bovine serum albumin (BSA) was kept above 99%, and the retention rate of Congo Red and Methyl blue dyes was 99.1% and 98.4%, respectively, this goes well beyond the PES membrane. In addition, through a series of conductivity tests, it has been proved that the conductive properties of composite membranes were greatly improved, and the conductivity of the MXene-PANI/PES composite membrane can reach 0.5 S m−1. After applying a negative voltage to the membrane, the negative charge around the surface of the membrane repels the negatively charged contaminant under the action of an electrostatic repulsion force, thereby the enrichment of pollutants on the membrane surface can be effectively reduced, and the FRR reached 93.7%. On the basis of ensuring membrane conductivity, we improved the permeability, selective separation, and anti-fouling ability of the membrane. This research shows great potential for the efficient development of an anti-fouling conductive separation membrane based on MXene.