Synthesis of Double Defects in g‐C₃N₄ to Enhance the H₂O₂ Production by Dual‐Electron O₂ Reduction

Abstract

In this work, the graphitic carbon nitride with -C≡N defects and S-defects (N₂ -SCN-4) was constructed. The H₂ O₂ production efficiency of N₂ -SCN-4 was 1423.3 μmol g^-1 h^-1 under the visible light (λ≥420 nm) irradiation, which was 15.4 times that of pristine g-C₃ N₄ . The -C≡N groups promote the adsorption of H⁺ and the S-defects provide the active center for the adsorption and activation of O₂ . Furthermore, the surface morphology, microstructure, and photoelectric chemical properties of samples were investigated by a series of characterizations, and the response range of N₂ -SCN-4 to visible light increases obviously. Meanwhile, the efficiency of photo-produced charge separation and the selectivity of H₂ O₂ production were discussed in detail. The experimental and characterization results confirmed that the charge separation efficiency and the selectivity of the 2e^- O₂ reduction reaction (ORR) were improved under the synergistic effect of the double defects. This work provides a strategy for improving the photocatalytic performance of photocatalysts.