Reasonable design of robust bifunctional oxygen catalysts from an electronic structure perspective is intriguing and challenging for the development of high active rechargeable zinc-air batteries (ZABs). In this study, the favorable regulation of the electronic structure of the cobalt oxide nanoclusters was firstly predicted by density functional theory (DFT) simulation, and then experimentally verified by confining sub-nanometer CoO_x clusters (0.86 nm) into the small pore of ZIF-8 derived N-doped nanomaterials (PNC) using a microporous MOFs confinement strategy. The confined effect of the MOF micropores not only enhanced the stability of the sub-nanometer cobalt oxide clusters, but also make it coupled with Co‒N_x to further regulate the electronic structure of the former, synergistic resulting in enhanced ORR/OER actives. As a result, the optimized 0.05CoO_x@PNC catalyst demonstrates outstanding bifunctional oxygen performance with a smaller potential gap of 0.67 V. Moreover, the rechargeable Zn-air batteries integrated 0.05CoO_x@PNC air cathode displays encouraging performance with a peak power density of 157.1 mW cm⁻², a specific capacity of 887 mAh g_Zn⁻¹at 10 mA cm⁻² and long-term cyclability for over 200 h, significantly outperforming the benchmark electrode couple consisted of Pt/C/RuO₂. DFT calculation further revealed that reducing particle size and coupling with Co‒N could effectively regulate the charge distribution of CoO_x nanoclusters and downshift the d-band center of Co adsorption sites in CoO_x nanoclusters, which reduced the reaction barrier of intermediate O₂* and OH* and ORR/OER overpotential, thus accelerating the overall ORR/OER kinetic process. This work offers a novel reference for the construction of a robust sub-nanometer cluster catalysts in the field of ZABs.

从电子结构的角度出发，合理设计坚固的双功能氧催化剂对于开发高活性可充电锌空气电池（ZAB）来说是充满挑战的挑战。在这项研究中，首先通过密度泛函理论（DFT）模拟预测了氧化钴纳米团簇的电子结构的良好调控，然后通过将亚纳米CoO _x团簇（0.86 nm）限制在ZIF小孔中进行了实验验证。-8派生了使用微孔MOF限制策略的N掺杂纳米材料（PNC）。MOF微孔的局限作用不仅增强了亚纳米氧化钴团簇的稳定性，而且使其与Co‒N _x耦合。进一步调节前者的电子结构，产生协同作用，从而增强ORR / OER活性物质。结果，经过优化的0.05CoO _x @PNC催化剂表现出出色的双功能氧性能，且电势差为0.67V。此外，集成有0.05CoO _x @PNC空气阴极的可再充电锌空气电池在峰值功率密度下显示出令人鼓舞的性能。的157.1 mW cm ^-2的比容量，10 mA cm ^-2的比容量887 mAh g _Zn ^-1和超过200 h的长期可循环性，明显优于由Pt / C / RuO ₂组成的基准电极对。DFT计算进一步揭示减少粒度和用Co-N耦合能有效调节的CoO的电荷分布_X纳米团簇和降档的d的以CoO CO吸附位点波段中心_X的纳米团簇，从而减少了中间的O反应屏障₂ *和OH *和ORR / OER的超电势，从而加快了整个ORR / OER的动力学过程。这项工作为在ZABs领域中构建坚固的亚纳米簇催化剂提供了新的参考。