Wang Yong, Qin Yunpu, Liu Sijia, Zhao Yongzhi, Liu Luan, Zhang Di, Zhao Shangqing, Liu Jianfang, Wang Jie, Liu Yadong, Wu Haoyang, Jia Baorui, Qu Xuanhui, Li Hao, Qin Mingli
Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China.
Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai 980-8577, Japan.
J Am Chem Soc. 2025 Apr 23;147(16):13345-13355. doi: 10.1021/jacs.4c18390. Epub 2025 Apr 8.
The scarcity of iridium (Ir) limits its widespread use in acidic oxygen evolution reaction (OER). Herein, mesoporous single-crystalline spinel CoO with atomically dispersed low-valence-state Ir has been developed to enable Ir's efficient and stable utilization. The surface Pourbaix diagram suggests that under acidic OER conditions, O* fully covers both CoO(111) and (110) surfaces, passivating Co sites but enhancing CoO's structural stability, a benefit further improved by Ir doping. Mesopores offer numerous loading sites for Ir single atoms (13.8 wt %), which activate the originally O*-passivated CoO(111) surface by creating high-intrinsic-activity Co-Ir bridge sites; meanwhile, Ir and Co leaching rates are reduced to about 1/4 and 1/5, respectively, compared to conventional Ir/CoO catalysts. Our catalyst exhibits a low η of 248 mV for over 100 h, showcasing its potential in water electrolysis.
铱（Ir）的稀缺性限制了其在酸性析氧反应（OER）中的广泛应用。在此，已开发出具有原子分散的低价态Ir的介孔单晶尖晶石CoO，以实现Ir的高效稳定利用。表面Pourbaix图表明，在酸性OER条件下，O完全覆盖CoO(111)和(110)表面，使Co位点钝化，但增强了CoO的结构稳定性，Ir掺杂进一步改善了这一优势。介孔为Ir单原子提供了大量负载位点（13.8 wt%），通过创建高本征活性的Co-Ir桥接位点激活原本被O钝化的CoO(111)表面；同时，与传统的Ir/CoO催化剂相比，Ir和Co的浸出率分别降低到约1/4和1/5。我们的催化剂在超过100小时内表现出248 mV的低过电位，展示了其在水电解中的潜力。
