Efficient optimization of electron/oxygen pathway by constructing ceria/hydroxide interface for highly active oxygen evolution reaction

Abstract

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.