Ruthenium Single‐Atom Modulated Protonated Iridium Oxide for Acidic Water Oxidation in Proton Exchange Membrane Electrolysers

• DOI: 10.1002/adma.202407394
• Publication Date: 2024-08-16T03:55:53Z
• Authors: Jialin Tang; Xinyan Liu; Xiaoxia Xiong; Qisheng Zeng; Yuan Ji; Chunxiao Liu; Jiawei Li; Hongliang Zeng; Yizhou Dai; Xinyan Zhang; Chengbo Li; Hongjie Peng; Qiu Jiang; Tingting Zheng; Chih‐Wen Pao; Chuan Xia
• Keywords: 01 natural sciences; 0104 chemical sciences

AbstractProton exchange membrane water electrolysers promise to usher in a new era of clean energy, but they remain a formidable obstacle in designing active and durable electrocatalysts for the acidic oxygen evolution reaction (OER). In this study, a protonated iridium oxide embedded with single‐atom dispersed ruthenium atoms (H3.8Ir1−xRuxO4) that demonstrates exceptional activity and stability in acidic water oxidation is introduced. The single Ru dopants favorably induce localized oxygen vacancies in the Ir─O lattice, synergistically strengthening the adsorption of OOH* intermediates and enhancing the intrinsic OER activity. In addition, the preferential oxidation of Ru and the electronegativity of the oxygen vacancies significantly stabilize the Ir─O active sites, improving the OER stability. Consequently, the H3.8Ir1─xRuxO4 catalyst shows an overpotential of 255 mV at 10 mA cm−2 and displays exceptional catalytic endurance in acidic electrolytes, surpassing 1100 h, representing a remarkable one‐order‐of‐magnitude increase in stability compared to that of pristine H3.8IrO4. A proton exchange membrane electrolyser utilizing the H3.8Ir1−xRuxO4 catalyst as an anode exhibits stable performance for more than 1280 h under a high current density of 2 A cm−2.