Chang Jiangwei, Shi Yuanyuan, Wu Han, Yu Jingkun, Jing Wen, Wang Siyang, Waterhouse Geoffrey I N, Tang Zhiyong, Lu Siyu
College of Chemistry and Pingyuan Laboratory, Zhengzhou University, Zhengzhou 450000, China.
School of Chemical Sciences, The University of Auckland, Auckland 1142, New Zealand.
J Am Chem Soc. 2024 May 15;146(19):12958-12968. doi: 10.1021/jacs.3c13248. Epub 2024 May 2.
The discovery of efficient and stable electrocatalysts for oxygen evolution reaction (OER) in acid is vital for the commercialization of the proton-exchange membrane water electrolyzer. In this work, we demonstrate that short-range Ru atom arrays with near-ideal Ru-Ru interatomic distances and a unique Ru-O hybridization state can trigger direct O*-O* radical coupling to form an intermediate O*-O*-Ru configuration during acidic OER without generating OOH* species. Further, the Ru atom arrays suppress the participation of lattice oxygen in the OER and the dissolution of active Ru. Benefiting from these advantages, the as-designed Ru array-CoO electrocatalyst breaks the activity/stability trade-off that plagues RuO-based electrocatalysts, delivering an excellent OER overpotential of only 160 mV at 10 mA cm in 0.5 M HSO and outstanding durability during 1500 h operation, representing one of the best acid-stable OER electrocatalysts reported to date. O-labeled operando spectroscopic measurements together with theoretical investigations revealed that the short-range Ru atom arrays switched on an oxide path mechanism (OPM) during the OER. Our work not only guides the design of improved acidic OER catalysts but also encourages the pursuit of short-range metal atom array-based electrocatalysts for other electrocatalytic reactions.
发现用于酸性析氧反应（OER）的高效稳定电催化剂对于质子交换膜水电解槽的商业化至关重要。在这项工作中，我们证明了具有近乎理想的Ru-Ru原子间距离和独特的Ru-O杂化态的短程Ru原子阵列能够在酸性OER过程中触发直接的O*-O自由基偶联，形成中间的O-O*-Ru构型，而不会生成OOH*物种。此外，Ru原子阵列抑制了晶格氧参与OER以及活性Ru的溶解。受益于这些优势，所设计的Ru阵列-CoO电催化剂打破了困扰RuO基电催化剂的活性/稳定性权衡，在0.5 M HSO中，在10 mA cm下仅具有160 mV的优异OER过电位，并且在1500小时的运行过程中具有出色的耐久性，是迄今为止报道的最佳酸稳定OER电催化剂之一。O标记的原位光谱测量以及理论研究表明，短程Ru原子阵列在OER过程中开启了一种氧化物路径机制（OPM）。我们的工作不仅指导了改进的酸性OER催化剂的设计，还鼓励了对用于其他电催化反应的基于短程金属原子阵列的电催化剂的探索。
