Cu3P/NiO@NF heterostructure for highly efficient alkaline oxygen evolution reaction

Abstract

Electrochemical water splitting for the generation of hydrogen and oxygen is a promising approach for energy storage technologies. Exploring a highly efficient and stable electrolytic water catalyst is the key to achieve economical and efficient hydrogen production. Heterostructured catalysts are composite materials distinguished by the presence of interfaces among their constituent components, which promote a synergistic effect that enhances catalytic performance. In this paper, we report a heterostructured catalyst Cu3P/NiO@NF, which is composed of Cu3P/NiO on three-dimensional nickel foam (NF) as electrocatalysts for water splitting. This study focuses on the fabrication of heterojunctions and the application of phosphorization techniques to improving the electrolytic water catalytic efficiency of Cu3P/NiO@NF. It was synthesized through hydrothermal synthesis and further optimized using high-temperature phosphorization to enhance its catalytic activity and long-term stability. Experimental results demonstrate that the Cu3P/NiO@NF material exhibits superior electrocatalytic performance, with a current density of 10 mA cm⁻² at an overpotential of 86 mV vs., while maintaining excellent stability in alkaline solutions (with Tafel slopes of 41.07 mV dec⁻¹). These findings suggest that Cu3P/NiO@NF heterostructures showed outstanding electrocatalytic performance for oxygen evolution reaction in 1 M KOH solution. The excellent electrocatalytic performance of Cu3P/NiO@NF could be ascribed to its heterostructures, offering plentiful of active sites and accelerating electrolyte penetration and leading to the synergetic effects. Additionally, the O vacancy caused by high-temperature phosphating occurred on the surface, increasing catalytic surface activity and improving oxygen splitting performance.