Dual Catalytic Mechanism of Co-Doped Amorphous Nickel Phosphate Catalysts in Nucleophilic Oxidation Reactions

Facing the fossil energy crisis and environmental issues, developing renewable energy is urgent, with green hydrogen being crucial in energy transition but electrolytic water hydrogen production has high costs needing solutions, such as replacing oxygen evolution reaction (OER) with organic oxidation reactions. Here, Co-doped amorphous nickel phosphate materials (Co-NiP_xO_y/NF) are synthesized via electrodeposition and applied as catalysts for the methanol oxidation reaction (MOR). The 10% Co-doped material demonstrates remarkable efficacy in catalyzing MOR. When compared to the OER, it reduced the applied potential required to reach a current density of 200 mA cm⁻² by 227 mV. During constant-current electrolysis at current densities ranging from 20 to 250 mA cm⁻², the Faraday efficiencies (FE) of the formate products consistently exceeded 90%, and the catalysts maintained stable electrolysis for 120 h. into and discussed the action mechanism of Co-NiP_xO_y/NF is delved, proposing a dual-mechanism model involving hydrogen vacancy oxygen and electrophilic OH^* species. These findings provide a solid theoretical foundation for the rational design and modification of catalysts, thereby paving the way for the development of a more efficient and cost-effective electrolytic water-based hydrogen production technology.