Improved H₂O₂ Photogeneration on KBr Doped-Polymeric Carbon Nitride Via Optimize the Oxygen Reduction Path

The photosynthesis of hydrogen peroxide (H₂O₂) from oxygen (O₂) represents a promising catalytic pathway, the limited efficiency of the oxygen reduction constitutes a primary barrier to enhancing production. In this content, alkali metal potassium (K⁺) and Br-doped g-C₃N₄ photocatalysts (K-CN) were successfully constructed by one-pot method. The introduction of K⁺ is not only beneficial to the transmission of space charge and the separation efficiency of photogenerated carriers, but also promotes the efficient production of H₂O₂ by 2e^- oxygen reduction reaction. The introduction of Br^- promotes O₂ converted to triplet state and triggers energy transfer process to increase ¹O₂ production, O₂ adsorption was facilitated through regulating the oxygen evolution (O₂→¹O₂), which is beneficial to the subsequent oxygen reduction process. The results showed that the H₂O₂ yield of 0.05 K-CN catalyst reached 26.0 mmol g^-1 h^-1, which was more than 5 times that of pure g-C₃N₄.