Active Edge Site‐Rich Carbon Nanocatalysts with Enhanced Electron Transfer for Efficient Electrochemical Hydrogen Peroxide Production

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 related to the electrocatalytic activity, suggesting that first outer‐sphere electron transfer to O2 is an important step governing the H2O2 production rate.

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