The Oxygen Evolution Reaction (OER) encounters an insurmountable kinetic bottleneck in water electrolysis due to the complex four-electron transfer process, while modulating the oxidation states of active sites holds promise for enhancing the OER performance. Here, we successfully prepare cobalt-based zeolitic imidazolate framework Co-ZIF-L on carbon cloth with high-valence Co sites (O-ZIF-CC) through a facile oxidation strategy by heat treatment under an air atmosphere and achieve rapid reconstruction from Co-ZIF-L to CoOOH during OER. The O-ZIF-CC, as an active MOF-based catalyst, exhibits a low overpotential (283 mV at 10 mA cm^–2). The excellent electrocatalytic activity of the O-ZIF-CC can be ascribed to the introduction of high-valence Co sites, facilitating reconstruction to generate CoOOH at low potentials. This work provides a feasible approach for understanding the optimization of the performance of MOF-based electrocatalysts through valence-state tuning.

中文翻译：

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通过用于析氧的钴的定制电子结构加速从 Co-ZIF-L 到 CoOOH 的重建

由于复杂的四电子转移过程，析氧反应（OER）在水电解中遇到了难以克服的动力学瓶颈，而调节活性位点的氧化态有望提高OER性能。在这里，我们通过在空气气氛下热处理的简单氧化策略，成功地在具有高价Co位点的碳布上制备了钴基咪唑酯骨架Co-ZIF-L（O-ZIF-CC），并实现了Co的快速重构OER 期间，-ZIF-L 变为 CoOOH。 O-ZIF-CC 作为一种活性 MOF 基催化剂，具有较低的过电势（10 mA cm ^–2时为 283 mV ）。 O-ZIF-CC优异的电催化活性可归因于高价Co位点的引入，有利于在低电位下重构生成CoOOH。这项工作为理解通过价态调节优化基于 MOF 的电催化剂的性能提供了一种可行的方法。