MXene-based membranes for advanced desalination: Properties, engineering strategies, and emerging applications

Membrane-based desalination is a promising solution, but conventional polymer membranes suffer from limitations in salt rejection, fouling resistance, and chemical stability. Two-dimensional MXene materials have emerged as promising alternatives: their lamellar structure, tunable interlayer spacing, surface terminations, and high electrical conductivity enable fast water transport and selective ion sieving. This comprehensive review provides an updated overview of recent advances in MXene-based membranes for various desalination processes (reverse osmosis, nanofiltration, forward osmosis, capacitive deionization, and membrane distillation). This work discusses fundamental MXene characteristics relevant to desalination including interlayer engineering, surface chemistry, and mechanical robustness and surveys a wide range of membrane architectures: pure MXene laminates, MXene–polymer composites, hybrid nanomaterial systems, and smart designs (bio-inspired, stimuli-responsive, and self-healing). This analysis reveals that MXene membranes consistently exhibit ultrahigh water permeability and high salt rejection across multiple desalination contexts, often surpassing conventional membranes. Strategies like crosslinking and composite fabrication have mitigated challenges of swelling and oxidation, while MXenes' intrinsic conductivity opens new antifouling and tunability mechanisms. By synthesizing knowledge from material design through system-level implementation, this review uniquely bridges fundamental science and practical deployment of MXene membranes, identifying remaining challenges such as long-term stability under realistic conditions and a deeper understanding of ion transport mechanisms, and outlines future research directions to advance scalable MXene-enabled desalination technologies.