Synergistic Co–Mn Interaction‐Induced Built‐In Electric Field Modulates Electron Redistribution for Efficient Oxygen Electrocatalysis in Zn‐Air Batteries

Developing highly efficient oxygen electrocatalysts to boost the kinetics of ORR and OER is essential to promoting the commercialization of Zn‐air batteries. Co and Mn‐based catalysts have been widely investigated in electrochemistry due to their variable valence states. Herein, Co‐MnO‐Mn 3 (PO 4 ) 2 synergetic composites (denoted CMO@NPC) are fabricated via phosphorylation pyrolysis of urea‐treated Co‐Mn‐MOF as ORR and OER catalysts for the rechargeable ZAB. Due to differences in diffusion coefficients, Mn 2+ is more readily transported to the surface, where it forms Mn 3 (PO 4 ) 2 outer framework to mitigate structural degradation during cycling. Moreover, the construction of Co‐Mn heterojunctions can modulate the electron distribution, break the original electronic symmetry, and thereby optimize the adsorption strength of reaction intermediates. As a result, the optimal CMO@NPC‐800 exhibits outstanding ORR and OER performance, delivering a potential difference of 0.701 V. DFT calculations reveal that the generation of a built‐in electric field in the Co‐MnO‐Mn 3 (PO 4 ) 2 system, and the Co‐Mn synergy optimizes the d‐band center, thereby significantly reducing the reaction barriers for both ORR and OER. The aqueous ZAB based on the CMO@NPC‐800 catalyst exhibits outstanding performance with a high peak power density (203.8 mW cm −2 ), a large specific capacity (793.5 mAh g −1 ), and long‐term charge–discharge durability (1695 cycles).