NaSCN‐Induced Cyano‐Rich Porous Graphitic Carbon Nitride with Sodium Dopant and Nitrogen Vacancies for Enhanced Photosynthesis of Hydrogen Peroxide

Abstract Defect engineering has been considered as an efficient and facile tactics to optimize the bandgap structure and improve the oxygen adsorption ability of graphitic carbon nitride (g‐C₃N₄). Herein porous g‐C₃N₄ with nitrogen vacancies and sodium dopant as well as cyano (─C≡N) groups has been successfully constructed by direct pyrolysis of melamine in the presence of cyano‐rich sodium thiocyanate (NaSCN). Moreover, the incorporation of NaSCN is interestingly found to induce the relative high content of ─C≡N groups compared to other inorganic sodium compounds (NaCl, NaOH, and Na₂SO₄), which has been experimentally demonstrated to be beneficial for extending the light absorption range and promoting the efficient separation of photo‐generated electron–hole pairs as well as improving the oxygen adsorption ability. Benefiting from the above features, the optimal photocatalyst exhibits high H₂O₂ yield of 438.2 µm within 4 h and excellent cyclic stability.