Fragmented Polymetric Carbon Nitride with Rich Defects for Boosting Electrochemical Synthesis of Hydrogen Peroxide in Alkaline and Neutral Media

Abstract Electrocatalytic oxygen reduction reaction via 2e − pathway is a safe and friendly route for hydrogen peroxide (H 2 O 2 ) synthesis. In order to achieve efficient synthesis of H 2 O 2 , it is essential to accurately control the active sites. Here, fragmented polymetric carbon nitride with rich defects (DCN) is designed for H 2 O 2 electrosynthesis. The multi‐type defects, including the sodium atom doping in six‐fold cavities, the boron atom doping at N−B‐N sites and the cyano groups, are successfully created. Owing to the synergistic effect of these defects, the fragmented DCN achieves a high H 2 O 2 production rate of 2.28 mol g cat. −1 h −1 and a high Faradic efficiency of nearly 90 % in alkaline media at 0.4 V vs. RHE in H‐type cell. In neutral media, the H 2 O 2 concentration produced by DCN can reach 1815 μM within 6 h at a potential of 0.2 V vs. RHE, and the H 2 O 2 production rate of DCN is 0.23 mol g cat. −1 h −1 . In addition, DCN shows excellent long‐term durability in alkaline and neutral media. This study provides a new approach for the development of the boron, nitrogen doped carbon‐based electrocatalysts for H 2 O 2 electrochemical synthesis.