Boosting Oxygen Evolution Reaction Performance on NiFe-Based Catalysts Through d-Orbital Hybridization

• DOI: 10.1007/s40820-024-01528-9
• Publication Date: 2024-09-26T07:01:54Z
• Authors: Xing Wang; Wei Pi; Sheng Hu; Haifeng Bao; Na Yao; Wei Luo
• Keywords: Technology; d-orbital coupling; Oxygen evolution reaction; T; NiFe-based catalysts; Anion exchange membrane electrolyzer; Article

AbstractAnion-exchange membrane water electrolyzers (AEMWEs) for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based catalysts. By introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units, the d-orbital and electronic structures can be adjusted, which is an important strategy to achieve sufficient oxygen evolution reaction (OER) performance in AEMWEs. Herein, the ternary NiFeM (M: La, Mo) catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this work. Experimental and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen, resulting in enhanced adsorption strength of oxygen intermediates, and reduced rate-determining step energy barrier, which is responsible for the enhanced OER performance. More critically, the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm−2 in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.