Advances and Promises of 2D MXenes as Cocatalysts for Artificial Photosynthesis

2D MXenes have received growing attention as highly active and earth‐abundant cocatalysts for photocatalytic applications, due to their merits including rich surface chemistry, excellent electrical conductivity, distinct carrier mobility, and good hydrophilicity. In this review, the research progress on MXenes and MXene‐based composites in photocatalysis are systematically summarized and discussed. Based on the theoretical and experimental studies, this review focuses mainly on the synthetic methods of MXenes, the roles of MXenes in photocatalysis, the design strategies for MXene‐based composites and the state‐of‐the‐art applications of these MXene‐based materials in photocatalytic reactions, including water splitting, CO 2 reduction, and nitrogen fixation. In addition, this review outlines the surface modification and enhancement mechanism from a material design and synthesis perspective, and highlights the pivotal challenges and potential opportunities in the field of MXene‐involved photocatalysis. Therefore, this review is expected to provide a useful reference for the development of MXene‐related photocatalytic applications.