Charge redistribution of Ru nanoclusters on Co3O4 porous nanowire via the oxygen regulation for enhanced hydrogen evolution reaction

Ru-based catalysts are widely studied for hydrogen evolution reaction. However, there is still a lack of research on which chemical environment is more favorable for the catalytic performance of Ru. In this work, Ru nanoclusters are loaded on porous Co3O4 nanowires (Ru/Co3O4 NWs), spherical aberration-corrected transmission electron microscope and extended X-ray absorption fine structure confirm the coordination environment of Ru with oxygen bond. Compare to Co nanowires, Ru/Co3O4 NWs have the better HER performance in alkaline medium (an overpotential of 30.96 mV at a current density of 10 mA cm−2, electrochemical areas of 4.31 mF cm−2). Theoretical calculation also demonstrates the charge redistribution of Ru through the O binding, which has a smaller |ΔGH*| value. Besides, Ru clusters are loaded on Co foam and further oxygen doped to achieve efficient and stable HER activity. This work put a deep insight into the role of oxygen regulation of Ru-based HER catalysts.