Preparation and performance of MXene-based electric field-responsive separation membranes

Membrane-based separation technologies often face a trade-off between selectivity and permeability, which represents a significant technical challenge in current research. In this study, vacuum-assisted surface deposition technology was utilized to co -deposit piperazine (PIP) and MXene onto a polyvinylidene fluoride (PVDF) microfiltration membrane. This was followed by interfacial polymerization, initiated by trimesoyl chloride (TMC), to form a polyamide (PA) network, resulting in the fabrication of a conductive thin-film nanocomposite membrane (CTFN-2). The results showed that the CTFN-2 membrane had a uniform PIP-TMC/MXene coating with a distinctive wrinkled structure on its surface, contributing to its high permeate flux and solute rejection. The membrane's separation performance was evaluated using a custom-built low-pressure cross-flow conductive membrane setup. The CTFN-2 membrane selectively rejected various ionic dyes under both positive and negative voltages, with an increased rejection rate for inorganic salts as the voltage rose. Notably, after being stored in deionized water for 180 days, the CTFN-2 membrane maintained stable dye separation performance. This research offers a novel approach for developing efficient and controllable separation membrane materials.