Fast and Stable Electrochemical Production of H2O2 by Electrode Architecture Engineering

Fast and stable production of hydrogen peroxide (H 2 O 2 ) through electrochemical pathways is crucial for wastewater treatment applications. With this objective, herein, we report an integrated and superaerophilic electrode composed of atomically dispersed Ni–O–C site-enriched carbon nanosheets (IS-NiOC electrode) for electrochemical oxygen reduction to produce H 2 O 2 . Both experimental and theoretical results have proven that atomically dispersed Ni–O–C sites enable a low overpotential (260 mV at 0.1 mA cm –2 ) and high selectivity (>90% at 0.0–0.5 V vs reversible hydrogen electrode (RHE)) in a neutral electrolyte. Compared with a commercial gas-diffusion electrode, the IS-NiOC electrode offers stronger affinity to oxygen bubbles and more robust three-phase contact points, resulting in high current density (∼106 mA cm –2 at 0.25 V vs RHE) and superior stability (∼200 h). These merits allow the application of the IS-NiOC electrode in an electro-Fenton-like process, which enables fast degradation of representative organic pollutants in both a steady state and a flow state.