Electrochemical hydrogen peroxide production enables clean and on‐site production of H2O2, for which highly active and selective electrocatalysts are of crucial importance. Here, we report a highly efficient, metal‐free carbon nanocatalyst that possesses abundant active, oxygenated graphitic edge sites. The edge site‐rich nanocarbon catalyst exhibits ~22 times higher activity for H2O2 production than a basal plane‐rich carbon nanotube with a H2O2 selectivity over 90%. The oxidative treatment further promotes the H2O2 generation activity to reach close to the thermodynamic limit. The optimized nanocarbon catalyst shows a very high H2O2 production activity, surpassing previously reported catalysts in alkaline media. Moreover, it can stably produce H2O2 for 16 hours with Faradaic efficiency reaching 99% and accumulated H2O2 concentration of 24 ± 2 mM. Importantly, we find that the heterogeneous electron transfer kinetics of the carbon‐based catalyst is closely relate
d to the electrocatalytic activity, suggesting that first outer‐sphere electron transfer to O2 is an important step governing the H2O2 production rate.
