Effective Hydrogen Peroxide Production from Electrochemical Water Oxidation

Abstract

The two-electron water oxidation reaction (2e– WOR) is progressively gaining traction as a sustainable approach for in situ electrosynthesis of hydrogen peroxide (H2O2). State-of-the-art 2e– WOR electrocatalysts have shown great promise at low electrical currents yet exhibit diminished electrocatalytic capabilities at larger current densities. Herein, by tailoring the boron doping level of boron-doped diamond (BDD) microfilms, we have fabricated an active, selective, and stable electrocatalyst for the 2e– WOR. Experimentally, we find that our modulated BDD films achieve a peak faradaic efficiency of 87%, as well as a record H2O2 production rate of 76.4 μmol cm–2 min–1, while maintaining a stable electrochemical performance for 10 h at 200 mA cm–2 in carbonate-based solutions. The results reported in this work firmly establish BDD as a primary catalyst candidate for large-scale implementation of the 2e– WOR and synchronously unlock new research avenues for the next-generation design of sp3-structured carbonaceous materials for anodic H2O2 electrosynthesis from water.