Engineering MXenes for electrochemical environmental pollutant sensing

Environmental pollutant sensing is essential to the sustainable development of human health and ecosystems. As a category of two-dimensional materials consisting of nitrides and carbides, MXenes have emerged as highly attractive candidates for electrochemical sensing of environmental pollutants, including toxic gases, harmful volatile organic compounds, and biologically relevant components, owing to their strong metallic conductivity, easy customization, abundant surface functional groups and large interlayer spacings. This comprehensive review firstly assesses the environmental pollutant sensing mechanism and modular MXene electrode fabrication methods. Subsequently, the research progress on MXenes is summarized by comparing their performances in environmental pollutant detection. Furthermore, ways to improve the electrochemical stability and selectivity of MXenes using different techniques are further discussed. Finally, challenges faced in this field and prospective directions for future research are suggested by integrating emerging technologies and interdisciplinary approaches. The key objective of this review is to motivate engineers and materials scientists to consider incorporating MXenes into technologies for environmental protection, thereby providing inventive solutions to urgent global issues.