Removal of selected inorganic contaminants by MXene-based pressure-driven membranes in water: A review

The growing demand for the efficient treatment of heavy metal and inorganic salts in water has driven extensive research into advanced membrane technologies. This review explores the potential of MXene-based pressure-driven membranes for removing selected heavy metal and inorganic species (Na+, K+, Mg2+, Ca2+, Al3+, F-, etc.) from water. MXenes, relatively new 2D materials with lamellar structure, tunable surface chemistry, and great hydrophilicity, when incorporated into membranes may offer enhanced removal efficiency with great water permeability compared to conventional membranes. This review summarizes the recent advancements in MXene and MXene membrane fabrication techniques, including effect of etching conditions on the properties of resulting MXene, strategies to fabricate of low- and high-pressure MXene-based membranes, and their application to remove selected heavy metals and inorganics in water. It critically assesses the efficacy of these membranes in removing heavy metals and other inorganic contaminants, with particular attention paid to the flux, removal efficiency, and influence of the operating conditions/physicochemical parameters. Furthermore, this review examines the feasibility of MXene-based membranes to mitigate the trade-offs between permeability and selectivity. However, it was identified challenges remain for long-term stability under complex water chemistry and scalable fabrication. Addressing these issues through coordinated material innovation, process optimization, and integrated systems is crucial to achieving the full potential of MXene-based membranes for water purification.