MXene-based composites for environmental applications: Recent advances

MXene-based composites have emerged as revolutionary materials for environmental applications, offering unprecedented capabilities in water treatment, air purification, and resource recovery. This review presents a comprehensive assessment of recent advances, spanning sustainable synthesis innovations to advanced composite design strategies. The unique combination of metallic conductivity, hydrophilic surface chemistry, and tunable interlayer spacing positions MXenes as highly versatile platforms for tackling critical environmental challenges. Significant progress has been demonstrated in heavy metal removal, with adsorption capacities exceeding 1000 mg/g, and in organic pollutant degradation via photocatalytic and Fenton-like pathways. Emerging synthesis approaches, including fluoride-free etching and electrochemical methods, have improved both scalability and material performance. MXene-based membranes are highlighted for their superior ion selectivity and dye rejection, while integration with metal–organic frameworks, layered double hydroxides, and polymer matrices has generated multifunctional composites with enhanced stability, selectivity, and durability. Photocatalytic applications further demonstrate outstanding hydrogen evolution and CO₂ reduction efficiencies, while MXene-based sensors achieve detection limits ranging from ppb to ppq levels for high-priority contaminants. The novelty of this review lies in its multi-dimensional performance analysis and integrative perspective, which unify experimental findings, theoretical models, and application prospects into a predictive framework. This approach reveals structure–property–function relationships, cross-cutting design principles, and optimization strategies across diverse environmental technologies, offering actionable insights for tailored composite development. By combining critical evaluation with forward-looking strategies, this review not only highlights the transformative potential of MXenes but also defines clear research pathways toward scalable and sustainable environmental technologies.