Influence of Transition Metal Doping on the Oxygen Evolution Reaction Activity of Nickel Phosphate Surface

Abstract

This study presents a comprehensive investigation of the oxygen evolution reaction (OER) activity on nickel phosphate (NiPO) surfaces doped with transition metals (Mn, Fe, Co, and Cu). By combining density functional theory calculations, the computational hydrogen electrode approximation, and microkinetic simulations, we demonstrate that transition metal doping significantly enhances OER performance compared to the pristine NiPO surface. The observed trends in overpotential values align with the oxygen adsorption energies on the doped surfaces, indicating a consistent improvement in catalytic activity. Despite the incorporation of different transition metals, the electronic profiles of surface nickel atoms remain largely unchanged, resulting in similar overpotential values at these sites. This suggests that the enhanced OER activity is primarily driven by the localized electronic states of the embedded transition metal dopants rather than changes in the nickel sites. Among the dopants studied, Fe and Mn exhibit the best OER performance, followed by Co and Cu.