Low Ruthenium Content Confined on Boron Carbon Nitride as an Efficient and Stable Electrocatalyst for Acidic Oxygen Evolution Reaction.

To date, only a few noble metal oxides exhibit the required efficiency and stability as oxygen evolution reaction (OER) catalysts under the acidic, high‐voltage conditions that exist during proton exchange membrane water electrolysis (PEMWE). The high cost and scarcity of these catalysts hinder the large‐scale application of PEMWE. Here, we report a novel OER electrocatalyst for OER comprised of uniformly dispersed Ru clusters confined on boron carbon nitride (BCN) support. Compared to RuO2, our BCN‐supported catalyst shows enhanced charge transfer. It displays a low overpotential of 164 mV at a current density of 10 mA cm−2, suggesting its excellent OER catalytic activity. This catalyst was able to operate continuously for over 12 h under acidic conditions, whereas RuO2 without any support fails in 1 h. Density functional theory (DFT) calculations confirm that the interaction between the N on BCN support and Ru clusters changes the adsorption capacity and reduces the OER energy barrier, which increases the electrocatalytic activity of Ru. [ABSTRACT FROM AUTHOR]