Enhancing oxygen adsorption via the synergistic catalysis of graphitic nitrogen carbon and antiperovskite ZnCNi in Zinc- Air batteries.

The key to the commercial available of Zinc Air batteries (ZABs) is to design and exploit the low-cost and high efficiency bifunctional oxygen electrocatalysts. Here, it is reported that a bifunctional electrocatalyst consisting of nitrogen-rich carbon nanotubes encapsulating antiperovskite ZnCNi nanoparticles grafted onto the surface of carbon nanofibers (ZnCNi-NCCF) for rechargeable ZABs. The electrocatalytic activity of ZnCNi-NCCF is promoted by the synergistic catalysis of graphitic nitrogen-doped carbon and antiperovskite ZnCNi. The ZnCNi-NCCF (1,3,3-9 h) with moderate graphitic nitrogen-doped carbon species exhibits low overpotentials (half-wave potential (E) = 0.75 V vs. RHE for oxygen reduction reaction (ORR), the potential to achieve current density of 10 mA cm (η) = 352 mV for oxygen evolution reaction (OER)) and Favourable stability. It was showed that graphitic-N-C in ZnCNi-NCCF enhances OOH adsorption to optimize activity of ORR by the Density functional theory (DFT) calculations. Additionally, the ZnCNi-NCCF-based ZABs stable charge-discharge cycling for 200 h and light up a 4 V light-emitting diode (LED) bulb for 12 h, thereby showcasing certain practical application prospects.