Coordination Environment Tuning of Nickel Sites by Oxyanions to Optimize Methanol Electro-oxidation Activity

To achieve zero-carbon economy, advanced anode catalysts are desirable for hydrogen production and biomass upgrading powered by renewable energy. Ni-based non-precious electrocatalysts are considered as potential candidates because of intrinsic redox attributes, but in-depth understanding and rational design of Ni site coordination still remain challenging. Here, we perform anodic electrochemical oxidation of Ni-metalloids (NiP, NiS, and NiSe) to in-situ construct different oxyanion-coordinated amorphous nickel oxyhydroxides (NiOOH-TO), among which NiOOH-PO shows optimal local coordination environment and boosts electrocatalytic activity of Ni sites towards selective oxidation of methanol to formate. Experiments and theoretical results demonstrate that NiOOH-PO possesses improved adsorption of OH* and methanol, and favors the formation of CHO* intermediates. The coordinated phosphate oxyanions effectively tailor the d band center of Ni sites and increases Ni-O covalency, promoting the catalytic activity. This study provides additional insights into modulation of active-center coordination environment via oxyanions for organic molecules transformation.