Although the electronic state of catalysts is strongly corrected with their oxygen evolution reaction (OER) performances, understanding the role of spin state in dynamic electronic structure evolution during OER process is still challenging. Herein, we developed a spin state regulation strategy to boost the OER performance of CoOOH through elemental doping (CoMOOH, M = V, Cr, Mn, Co and Cu). Experimental results including magnetic characterization, in situ X‐ray absorption spectroscopy, in situ Raman and density functional theory calculations unveil that Mn doping could successfully increase the Co sites from low spin state to intermediate spin state, leading to the largest lattice distortion and smallest energy gap between dxy and dz2 orbitals among the obtained CoMOOH electrocatalysts. Benefiting from the promoted electron transfer from dxy to dz2 orbital, facilitated formation of active high‐valent *O‐Co(IV) species at applied potential, and reduced energy barrier of rate‐determining step, the CoMnOOH exhibits the highest OER performance. Our work provides significant insight into the correction between dynamic electronic structure evolution and OER performance by understanding the role of spin state regulation in metal oxyhydroxides, paving a new avenue for rational design of high‐activity electrocatalysts.

中文翻译：

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了解自旋态在羟基氧化钴水氧化中的作用


尽管催化剂的电子态与其析氧反应（OER）性能密切相关，但了解自旋态在 OER 过程中动态电子结构演化中的作用仍然具有挑战性。在此，我们开发了一种自旋态调节策略，通过元素掺杂（CoMOOH，M = V，Cr，Mn，Co 和 Cu）来提高 CoOOH 的 OER 性能。包括磁表征、原位X射线吸收光谱、原位拉曼和密度泛函理论计算在内的实验结果表明，Mn掺杂可以成功地将Co位点从低自旋态增加到中间自旋态，从而导致最大的晶格畸变和最小的能量所得 CoMOOH 电催化剂中 dxy 和 dz2 轨道之间的间隙。受益于促进电子从 dxy 到 dz2 轨道的转移，促进在施加电位下形成活性高价 *O-Co(IV) 物质，以及降低速率决定步骤的能垒，CoMnOOH 表现出最高的 OER 性能。我们的工作通过了解金属羟基氧化物中自旋态调节的作用，为动态电子结构演化和 OER 性能之间的校正提供了重要的见解，为合理设计高活性电催化剂铺平了新途径。