Spontaneous Cation Exchange-Induced Iron Doping in Ni(OH)₂ for Enhanced Oxygen Evolution Reaction

The oxygen evolution reaction (OER) is pivotal in clean energy technologies, such as fuel cells and electrolyzers. However, their sluggish kinetics significantly hampers the efficiency of these devices. To boost the progress of the OER, developing low-cost and high-activity OER electrocatalysts is necessary. Due to their low cost, nickel and nickel-based electrodes have enormous research potential for water electrolysis. This study presents the fabrication of iron-doped Ni(OH) 2 (Fe-Ni(OH) 2 ) nanostructures on porous nickel foam substrates using electrodeposition and cation exchange. The Fe-Ni(OH) 2 /NF catalysts demonstrated prominent OER performance with an overpotential of 155 mV at 10 mA cm –2 and a Tafel slope of 59.7 mV dec –1, showing excellent stability for about 50 h. The study also simulated hydrogen production from solar power using Fe-Ni(OH) 2 /NF as an anode electrocatalyst, revealing the possibility of integrating renewable energy with hydrogen production. This work introduces a simple and rapid method for preparing high-performance and stable electrocatalysts, which will provide inspiration for the development and utilization of nonprecious metal-based catalysts.