In situ preparation of Fe-doped NiMoO4 nanoflower clusters as efficient electrocatalysts for oxygen evolution reaction and overall water splitting

Water electrolysis for hydrogen production has attracted significant scientific interest because it is sustainable, pure, and environmentally benign. Nevertheless, the slow rate of the oxygen evolution reaction (OER) during electrolytic water splitting greatly impedes the progress of its development, leading to higher energy consumption and higher costs during hydrogen production. Herein, Fe-doped NiMoO4 nanoflower clusters on nickel foam (Fe-NiMoO4-clusters/NF) as a superior electrocatalyst for the OER via a facile hydrothermal synthesis method. The material delivers excellent electrocatalytic performance at optimal Fe doping level (4%) with low overpotentials of 170 mV@10 mA cm−2 and 240 mV@100 mA cm−2, a small Tafel slope, and long-term stability. Remarkably, the overall water splitting system assembled with the designed material and NiMoO4-clusters/NF exhibits superior stability and a low driving voltage. A comprehensive analysis indicates that Fe doping is crucial to the structure and electrocatalytic properties of NiMoO4. Fe-doped NiMoO4-clusters can serve as stable and efficient OER electrocatalysts in alkaline electrolytes.