Niu Ziqiang, Qiao Zelong, Sun Panpan, Chen Jingzhao, Wang Shitao, Huo Feng, Cao Dapeng
State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China.
Longzihu New Energy Laboratory, Zhengzhou Institute of Emerging Industrial Technology, Zhengzhou, 450000, China.
Small. 2025 Jun;21(23):e2502088. doi: 10.1002/smll.202502088. Epub 2025 Apr 17.
Developing highly efficient and stable Pt/Ir-free bifunctional catalysts is very urgent for lowering the catalyst cost of proton exchange membrane water electrolyzer (PEMWE). Herein, a single-atom Sb-doped RuSbO bifunctional catalyst is developed for ultra-stable PEMWE. RuSbO exhibits excellent stability with a long-term operation of 150 h for oxygen evolution reaction (OER) and 300 h for hydrogen evolution reaction (HER) at 100 mA cm in acidic media, respectively. Impressively, the PEMWE with RuSbO as bifunctional catalysts only needs 1.72 to reach 1.0 A cm, and can maintain stable operation for 200 h at 200 mA cm. The in situ Raman and molecular probe methods reveal that the single-atom Sb doping can reconstruct the interfacial water structure on the surface of RuSbO, resulting in an enriched supply of free water, accelerating the deprotonation process and reducing the local acidity of the catalyst surface, thereby improving the acidic OER activity and stability. Density functional theory calculations further confirm the above experimental results. In short, this work reveals that Sb is an outstanding structural stabilizer, and single-atom Sb-doping can maximize the OER stability of Ru-based catalysts in acid, which provides a useful strategy for designing ultra-stable electrocatalysts for PEMWE.
开发高效稳定的无铂/铱双功能催化剂对于降低质子交换膜水电解槽（PEMWE）的催化剂成本非常迫切。在此，开发了一种单原子锑掺杂的RuSbO双功能催化剂用于超稳定的PEMWE。RuSbO在酸性介质中分别在100 mA cm下对析氧反应（OER）进行150小时的长期运行和对析氢反应（HER）进行300小时的长期运行时表现出优异的稳定性。令人印象深刻的是，以RuSbO作为双功能催化剂的PEMWE仅需1.72就能达到1.0 A cm，并能在200 mA cm下保持200小时的稳定运行。原位拉曼和分子探针方法表明，单原子锑掺杂可以重构RuSbO表面的界面水结构，导致自由水供应丰富，加速去质子化过程并降低催化剂表面的局部酸度，从而提高酸性OER活性和稳定性。密度泛函理论计算进一步证实了上述实验结果。简而言之，这项工作表明锑是一种出色的结构稳定剂，单原子锑掺杂可以最大限度地提高Ru基催化剂在酸性条件下的OER稳定性，这为设计用于PEMWE的超稳定电催化剂提供了一种有用的策略。
