Boosting Activity and Stability of Electrodeposited Amorphous Ce-Doped NiFe-Based Catalyst for Electrochemical Water Oxidation

Abstract

NiFe-based hydroxides are considered as promising nonprecious catalysts for water oxidation due to their low cost and easy preparation. However, the rational design of NiFe-based electrocatalysts remains a great challenge to address the sluggish reaction kinetics and severe deactivation problems for oxygen evolution reaction (OER). Here, the authors report a facile approach to fabricate an amorphous Ce-doped NiFe hydroxide catalyst, which enables high activity and outstanding stability toward OER in alkaline media. The overpotential of electrodeposited amorphous Ce-doped NiFe is only 195 mV at 10 mA cm⁻². Meanwhile, the durability of the amorphous Ce-doped NiFe is maintained for 300 h at 100 mA cm⁻². The comprehensive characterization results reveal that the improved electrochemical performance of the amorphous Ce-doped NiFe catalyst is originated from the favorable oxidation transition of active sites enabled by Ce-doping. It is a very good strategy to introduce highly oxidized state ions to regulate the NiFe-based catalyst to improve the catalytic activity and stability.