Unveiling Favorable Microenvironment on Porous Doped Carbon Nanosheets for Superior H2O2 Electrosynthesis in Neutral Media

Abstract

Designing effective electrocatalysts tailored for targeted reactions requires fundamental insights into the structure dependence of the reaction microenvironment. Herein, inspired by finite element simulations, N,O co-doped carbon nanosheets featuring a hierarchical micro/mesoporous structure to form an oxygen-rich and local alkaline-like microenvironment for the two-electron oxygen reduction reaction (2e− ORR) in a neutral medium are designed. The in situ and ex situ test results confirmed that the micro/mesoporous carbon architecture can elevate the local pH and accelerate the generation of intermediates (*O2, *OOH), leading to high-efficiency H2O2 production. Utilizing this favorable microenvironment, N,O-CNS0.5 demonstrated exceptional H2O2 electrosynthesis performance in neutral media, achieving a superior H2O2 yield rate (6705 mmol gcatalyst−1 h−1 in a flow cell). Additionally, comparative experiments and density-functional theory calculations provided confirmation of the bi-doping of N and O as the active origin responsible for the electrochemical 2e− ORR. This study synergistically manipulates the reaction microenvironment and active sites, providing an opportunity for efficient H2O2 electro-production in a neutral medium.