A "Pre-Division Metal Clusters" Strategy to Mediate Efficient Dual-Active Sites ORR Catalyst for Ultralong Rechargeable Zn-Air Battery

Abstract

To conquer the bottleneck of sluggish kinetics in cathodic oxygen reduction reaction (ORR) of metal-air batteries, catalysts with dual-active centers have stood out. Here, a "pre-division metal clusters" strategy is firstly conceived to fabricate a N,S-dual doped honeycomb-like carbon matrix inlaid with CoN₄ sites and wrapped Co₂ P nanoclusters as dual-active centers (Co₂ P/CoN₄ @NSC-500). A crystalline {Co^II ₂ } coordination cluster divided by periphery second organic layers is well-designed to realize delocalized dispersion before calcination. The optimal Co₂ P/CoN₄ @NSC-500 executes excellent 4e^- ORR activity surpassing the benchmark Pt/C. Theoretical calculation results reveal that the CoN₄ sites and Co₂ P nanoclusters can synergistically quicken the formation of *OOH on Co sites. The rechargeable Zn-air battery (ZAB) assembled by Co₂ P/CoN₄ @NSC-500 delivers ultralong cycling stability over 1742 hours (3484 cycles) under 5 mA cm^-2 and can light up a 2.4 V LED bulb for ≈264 hours, evidencing the promising practical application potentials in portable devices.

Keywords: DFT Calculations; Dual-Active Centers; Oxygen Reduction Reaction; Pre-Division Metal Clusters; Zn-Air Batteries.