Engineering Thin-Film Nanocomposite Membranes with 2D Nanomaterials for Water Purification: Progress, Challenges, and Future Perspectives

The engineering of thin-film nanocomposite (TFN) membranes with two-dimensional (2D) nanomaterials has emerged as a transformative strategy in water purification. By integrating nanofillers such as graphene oxide, MXenes, and metal-organic frameworks into the polyamide (PA) selective layer, TFN membranes effectively overcome the conventional permeability–selectivity trade-off seen in thin-film composite membranes. These 2D nanomaterials offer enhanced hydrophilicity, reduced PA thickness, improved antifouling behavior, and additional water-transport channels, leading to higher water flux, greater salt rejection, and improved chemical resistance. This review highlights recent progress in the design and performance of 2D nanomaterial-incorporated TFN membranes for desalination and wastewater treatment. Key performance metrics are critically analyzed, including permeability, selectivity, fouling resistance, and structural stability. Despite significant advancements, challenges remain, particularly in nanomaterial dispersion, polymer compatibility, large-scale fabrication, and long-term operational stability. Strategies such as surface functionalization, nanofiller hybridization, and interfacial engineering are discussed to address these issues. Future perspectives emphasize the need for scalable fabrication techniques, robust integration of nanomaterials with polymers, and the development of multifunctional membranes tailored for diverse water-treatment applications beyond desalination.