MoZn-based high entropy alloy catalysts enabled dual activation and stabilization in alkaline oxygen evolution
Yunjie Mei, Jinli Chen, Qi Wang, Yaqing Guo, Hanwen Liu, Wenhui Shi, Lin Cheng, Yifei Yuan, Yuhua Wang, Bao Yu Xia, Yonggang Yao
Abstract
It remains a grand challenge to develop electrocatalysts with simultaneously high activity, long durability, and low cost for the oxygen evolution reaction (OER), originating from two competing reaction pathways and often trade-off performances. The adsorbed evolution mechanism (AEM) suffers from sluggish kinetics due to a linear scaling relationship, while the lattice oxygen mechanism (LOM) causes unstable structures due to lattice oxygen escape. We propose a MoZnFeCoNi high-entropy alloy (HEA) incorporating AEM-promoter Mo and LOM-active Zn to achieve dual activation and stabilization for efficient and durable OER. Density functional theory and chemical probe experiments confirmed dual-mechanism activation, with representative Co-Co † -Mo sites facilitating AEM and Zn-O † -Ni sites enhancing LOM, resulting in an ultralow OER overpotential (η 10 = 221 mV). The multielement interaction, high-entropy structure, and carbon network notably enhance structural stability for durable catalysis (>1500 hours at 100 mA cm −2 ). Our work offers a viable approach to concurrently enhance OER activity and stability by designing HEA catalysts to enable dual-mechanism synergy.