BCNO Nanosheet Supported Co3O4 Nanoparticles as an Enhanced Electrocatalyst for Oxygen Evolution Reaction

Cobalt trioxide is a promising cobalt-based oxygen evolution reaction (OER) electrocatalyst, and its OER performance is limited by its low ratio of Co3+ to Co2+ ions and the dispersibility of nanoparticles. Here we report a simple method to improve the OER catalytic activity via loading Co3O4 nanoparticles onto boron carbon oxynitride (BCNO) nanosheets, which greatly decreases the overpotential (∼80 mV) and improves the stability of the Co3O4 nanoparticles. The Co3O4/BCNO nanocomposite exhibits a good OER performance with a small Tafel slope of 57.58 mV/dec and a low overpotential of 317 mV (vs RHE at 10 mA/cm2) under alkaline conditions. The high OER performance of the Co3O4/BCNO nanocomposite is induced by the larger active surface area and higher ratio of Co3+ to Co2+ ions as well as the formation of Co-N chemical bonds.