Defect Engineering in 2D Photocatalytic Materials for CO2 Reduction

Two-dimensional (2D) photocatalysts are promising candidates for efficient conversion of inexhaustible solar energy into clean fuels and chemicals. Defect engineering is proved to be a powerful tool to promote their performance in photocatalytic CO2 reduction reaction. This review concisely summarizes the recent progress in design and controllable creation of defects in 2D photocatalysts, together with an introduction of the characterization techniques that can be adopted to unveil the atomic arrangement and electronic structure of the defects. Moreover, the impacts of the defect states on the functions of 2D photocatalysts in three basic steps of photocatalytic CO2 process are discussed. Finally, the challenges and future possibilities in developing advanced 2D photocatalysts for improving the performance of CO2 reduction via defect engineering are outlined.