Fabrication of MXene-based membranes and their application in per- and polyfluorinated substances removal: Comparison with commercial membranes, challenges, and future improvements

In the past decade, per- and polyfluorinated substances (PFAS) have garnered significant attention due to their widespread presence and detrimental environmental and health impacts. These compounds exhibit exceptional hydrophobicity, oleophobicity, chemical stability, and resistance to biodegradation, posing a significant threat to living organisms, particularly mammals. Numerous technologies have been employed for PFAS removal in which membrane filtration stands out as a highly effective approach, capable of removing different types of PFAS (anionic, cationic, and zwitterionic) with efficiencies exceeding 99 %. The advent of MXenes, a class of two-dimensional transition metal nitrides, oxycarbides, carbonitrides, and carbides, has revolutionized water treatment. MXene-based membranes, with their diverse elemental structure and ability to accommodate multiple surface functional groups, offer exceptional promise for PFAS removal. For the first time, all studies about PFAS removal via MXene-based membranes were summarized in this review article, and their performance was compared to commercial membranes. Moreover, the fabrication methods of MXene-based membranes were discussed in details. Finally, authors have given numerous suggestions about the future of PFAS removal via MXene-based membranes and explained what is missing currently.