The development of earth-abundant and cost-effective electro-catalysts at the air cathodes for both oxygen reduction and evolution reactions (ORR and OER) with sluggish kinetics are central to the overall performance of rechargeable metal-air batteries, remaining an issue that is gaining increasing interest in recent years. Herein, we report a nitrogen-doped mesoporous carbon supported clustered CoO_x composite catalyst (CoO_x/NMC) synthesized from the anchored atomically dispersed CoOOH species by an efficient two-step nucleation method. Due to the synergistic and size effects, CoO_x/NMC exhibits an enhanced bifunctional electrocatalytic performance in alkaline media than the state of the art commercial Pt/C catalyst for ORR and the OER catalyst (Ir/C). More importantly, the advanced CoO_x/NMC catalyst enables recharge Zn-air batteries (ZABs) to achieve long-term cycling performance over 400 ​h by galvanostatic charge-discharge at current density of 10 ​mA ​cm⁻² with high efficiency, suggesting a very promising alternative to the conventional Pt/C and Ir/C catalysts for an air cathode.

在空气阴极上开发出地球上富裕且具有成本效益的电催化剂，用于动力学还原反应缓慢的氧还原和放出反应（ORR和OER），这对可充电金属空气电池的整体性能至关重要，这仍然是一个问题近年来越来越受到关注。在本文中，我们报告了通过高效的两步成核方法，由锚定的原子分散的CoOOH物种合成的氮掺杂的介孔碳载簇状CoO _x复合催化剂（CoO _x / NMC）。由于协同效应和尺寸效应，CoO _x/ NMC在碱性介质中的双功能电催化性能高于ORR和OER催化剂（Ir / C）的最新工业Pt / C催化剂。更重要的是，先进的CoO _x / NMC催化剂可通过恒电流充放电以10 mA cm ^-2的电流密度高效地对Zn-空气电池（ZABs）进行充电，从而在400 h内实现长期循环性能，提出了对于空气阴极的常规Pt / C和Ir / C催化剂非常有希望的替代品。