Jiayi Li, Yiming Zhu, Changyuan Li, Qian Zhang, Ju Rong, Shasha Guo, Nicolás Alonso‐Vante, Long Yang, Min‐Hsin Yeh, Wei‐Hsiang Huang, Xiaohua Yu, Hongfei Cheng, Jiwei Ma
and noteworthy durability in an anion exchange membrane water electrolyzer. Time-resolved operando Quick X-ray absorption spectroscopy reveals rapid Mo leaching followed by structural reconstruction, culminating in the NiOOH formation. Theoretical calculations suggest a likely "complementary amorphous-electronic" mechanism. It shows that the amorphous structure exposes more active sites and favors the adsorption of intermediates, while Ru single atoms finely modulate the electronic structure. These valuable insights highlight the design of high-performance OER electrocatalysts based on metal single atoms anchored on amorphous oxides.