“…Although the g-C 3 N 4 -based photocatalysis has been fully discussed in many recent review articles( Li et al, 2020a ; Li et al, 2021a ; Chen et al, 2021 ; Xing et al, 2021 ; Zhu et al, 2021 ; Chen et al, 2022b ), a relative focus review about doping strategies to modify g-C 3 N 4 for improving the efficiency of water splitting is still lacking. Compared with other effective strategies for modification of g-C 3 N 4 , like heterojunction construction, defect introduction, and nanostructure controlling, the modification process of g-C 3 N 4 can be comparatively simplified by element doping to tune the band gap, which considerably broadens the light absorption and accelerates the electron-hole pair separation ( Li et al, 2020b ).…”