Jiang Xue, Zhu Jie, Jiang Minxia, Zhang Pengfei, Wen Wei, Cai Wenwen, Ding Yupei, Sun Pingping, Cao Minhua
Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, P. R. China.
State Key Laboratory of Tropic Ocean Engineering Materials and Materials Evaluation, College of Marine Science and Engineering, Hainan University, Haikou, 570228, P. R. China.
Adv Mater. 2025 Apr 13:e2503354. doi: 10.1002/adma.202503354.
The acidic oxygen evolution reaction (OER) electrocatalysts for proton exchange membrane electrolyzer (PEMWE) often face a trade-off between activity and stability due to inherent linear relationship and overoxidation of metal atoms in highly oxidative environments, while following the conventional adsorbate evolution mechanism (AEM). Herein, a favorable AEM-derived proton acceptor-electron donor mechanism (PAEDM) is proposed in RuO by constructing interstitial-substitutional mixed solid solution structure (denoted as C,Ta-RuO), which can effectively break the activity-stability trade-off of RuO in acidic OER. In situ spectroscopy experiments and theoretical calculations reveal that the interstitial C as the proton acceptor reduces the deprotonation energy barrier, enhancing catalytic activity, while the substitutional Ta as the electron donor donates electrons to the Ru sites via bridging oxygen, weakening the Ru─O bond covalency and preventing over-oxidation of surface Ru, thereby ensuring long-term stability. Under the guidance of this mechanism, the optimized C,Ta-RuO simultaneously achieves far low overpotential (η = 171 mV) and ultra-long stability (over 1300 h) for the acidic OER. More remarkably, a homemade PEMWE using C,Ta-RuO as the anode also shows high water splitting performance (1.63 V@1 A cm). This work supplies a novel strategy to guide future developments on efficient OER electrocatalysts toward water oxidation.
用于质子交换膜电解槽（PEMWE）的酸性析氧反应（OER）电催化剂，由于在高氧化环境中金属原子存在固有的线性关系和过氧化现象，在遵循传统吸附质演化机理（AEM）时，往往面临活性与稳定性之间的权衡。在此，通过构建间隙 - 取代混合固溶体结构（记为C,Ta - RuO），在RuO中提出了一种有利的源自AEM的质子受体 - 电子供体机理（PAEDM），该机理可有效打破RuO在酸性OER中的活性 - 稳定性权衡。原位光谱实验和理论计算表明，作为质子受体的间隙C降低了去质子化能垒，提高了催化活性，而作为电子供体的取代Ta通过桥连氧向Ru位点提供电子，削弱了Ru─O键的共价性并防止表面Ru的过度氧化，从而确保了长期稳定性。在该机理的指导下，优化后的C,Ta - RuO在酸性OER中同时实现了极低的过电位（η = 171 mV）和超长的稳定性（超过1300小时）。更值得注意的是，使用C,Ta - RuO作为阳极的自制PEMWE也表现出高析水性能（1.63 V@1 A cm）。这项工作为指导未来高效OER电催化剂用于水氧化的发展提供了一种新策略。
