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.