A Critical Review of Two-Dimensional Nanomaterial MXenes and their Applications in Water Treatment

Environmental pollution has accelerated and intensified because of the acceleration of industrialization, therefore fabricating excellent materials to remove hazardous pollutants has become inevitable. MXenes as emerging transition metal nitrides, carbides, or carbonitrides with high conductivity, hydrophilicity, excellent structural stability, and versatile surface chemistry, become ideal candidates for water treatment. This review summarizes recent advances in the synthesis and applications of MXenes as adsorbents, photocatalysts, and separation membranes for water purification. Extensive information related to the synthesis and applications of MXenes for water treatment and their associated patents were collected. This review has given a comprehensive survey of the recently reported 2D nanomaterial (NM) MXenes which are used in various water treatment applications. The effects of structure control, surface modification and composite of MXene on the adsorption performance of MXene and the formation of effective heterojunction, photocatalysts separation membrane were discussed in detail. The existing problems in the water treatment applications of MXene were summarized and analyzed. The overview also features discussions on the computational attempts, biocompatibility, and environmental impact in the exploration of MXenes for applications of water treatment, highlighting the challenges and opportunities of these advanced 2D NMs. The prospects of designing MXene based water treatment materials with excellent performance were put forward.