Elemental Charge Engineering in Cobalt and Cobalt–Phosphide Interface for Enhanced Oxygen Evolution and Urea Oxidation Reactions

The development of cost-effective electrocatalysts with high performance for oxygen evolution and urea oxidation reaction (OER/UOR) is desirable but remains a great challenge. Here, we report a facile strategy for boron-doping cobalt and cobalt–phosphide interfacial electrocatalysts (B–Co/Co2P) for bifunctional OER/UOR. By virtue of B doping, the abundant exposed active sites as well as enhanced electrical conductivity can efficiently improve charge migration of the heterogeneous interfacial sites. Therefore, the obtained B–Co/Co2P electrocatalysts exhibit bifunctional OER/UOR activities with an outstanding overpotential of 284 and 107 mV at an industrial current density of 100 mA cm–2, respectively. Such an excellent catalytic performance is attributed to the fact that the B dopant adjusts the electron distribution of interfacial catalytic sites and optimizes the adsorption/desorption of reaction intermediate species, as well as reduces the energy barriers of water oxidation. Furthermore, the setup two-electrode cell requires merely overpotentials of 280.7 and 56.9 mV to drive 10 mA cm–2 with robust stability in water splitting and urea electrolysis, respectively. Overall, this report provides a strategy to construct bifunctional OER/UOR catalysts with high efficiency for hydrogen generation.