Cross‐Scale Synergy in MOF‐Derived Catalysts: Bonded Fe–Co Atom Pairs with Oxygen Ligands Unlocking Enhanced Oxygen Reduction via d‐Orbital Modulation

Integrating cross-scale active sites-single atoms (SA), atom pairs (AP), and nanoparticles-into a unified catalytic system presents a promising strategy for advancing oxygen reduction reaction (ORR), an extremely important process in energy conversion. However, the synergistic interplay among these sites and their mechanistic roles remains poorly understood. Here, we report a novel catalyst (3) featuring Zn_SA, bonded Fe-Co_AP with dual-oxygen ligands, and Fe_0.72Co_0.28 nanoparticles, synthesized via pyrolysis of a metal matrix-engineered metal-organic framework (MOF). Combined experimental/theoretical studies reveal the bonded Fe-Co_AP sites with dual oxygen ligands serve as the primary active centers, where the Co_Fe-CoAP bonded O ligand directly participates in the formation of the *OH intermediate, and the FeO_Fe-CoAP modulates the Co d-band center (ɛ_d), facilitating *OH desorption-the ORR rate-limiting step. Meanwhile, adjacent metal nanoparticles and single Zn atom collectively assist intermediate adsorption strengths and co-activation of adsorbed O₂. This promising synergy endows 3 with exceptional ORR activity, enabling a Zn-air battery with high-power/gravimetric energy density. This work establishes a MOF-based platform for electrocatalyst design while elucidating the critical role of oxygen-bridged metal pairs in regulating reaction pathways.