Efficient Optimization of Electron/Oxygen Pathway by Constructing Ceria/Hydroxide Interface for Highly Active Oxygen Evolution Reaction

Owing to the unique electronic properties, rare-earth modulations in noble-metal electrocatalysts emerge as a critical strategy for a broad range of renewable energy solutions such as water-splitting and metal–air batteries. Beyond the typical doping strategy that suffers from synthesis difficulties and concentration limitations, the innovative introduction of rare-earth is highly desired. Herein, a novel synthesis strategy is presented by introducing CeO₂ support for the nickel–iron–chromium hydroxide (NFC) to boost the oxygen evolution reaction (OER) performance, which achieves an ultralow overpotential at 10 mA cm⁻² of 230.8 mV, the Tafel slope of 32.7 mV dec⁻¹, as well as the excellent durability in alkaline solution. Density functional theory calculations prove the established d–f electronic ladders, by the interaction between NFC and CeO₂, evidently boosts the high-speed electron transfer. Meanwhile, the stable valence state in CeO₂ preserves the high electronic reactivity for OER. This work demonstrates a promising approach in fabricating a nonprecious OER electrocatalyst with the facilitation of rare-earth oxides to reach both excellent activity and high stability.