A p-d block synergistic effect enables robust electrocatalytic oxygen evolution

Oxygen evolution reaction (OER), occurring at the anode of electrochemical water splitting requires a comprehensive understanding of oxygen electrocatalysis mechanism to optimize its efficiency. Atomically dispersed transition metal supported by nitrogen-doped carbon is featured with excellent catalytic performance. Herein, we report a Mg/Co bimetal site which utilizes Mg 3p electrons with strong binding of *OH (the first key reaction intermediates in the free energy diagram) to trigger the OER reaction and Co 3d itinerant character to regulate the binding strength of *O. Benefiting from the fine-tuned adsorption/desorption possesses, the optimized catalyst delivers superior OER activity with low overpotential, i.e., 310 mV at a current density of 10 mA/cm2 and 455 mV at 100 mA/cm2. Moreover, the current density is able to be maintained at 10 mA/cm2 for 10 h, consistent with the theoretical simulations for oxidization process, which demonstrates stable configurations after multiple *OH modification, revealing robust applicability in alkaline medium.