Cross‐Scale Orchestration of Sublayer Axially N‐Bridged Fe Single Atoms Within Diffusion‐Oriented Matrix for Efficient Oxygen Reduction

ABSTRACT Symmetry perturbation of planar FeN 4 moieties in Fe─N─C single‐atom catalysts holds great promise for elevating oxygen reduction reaction (ORR) performance, yet atomically precise coordination engineering of thermodynamically stable configurations with efficient O 2 mass‐transport integration remains challenging. Herein, a nitrogen‐mediated thermal activation strategy is proposed to construct a sublayer‐engineered Fe‐N 5 single‐atom catalyst, termed FeN 5 ‐ANDCL, featuring an axially N‐bridged dual‐carbon‐layer architecture integrated into a hollow carbon framework. The elaborately engineered FeN 5 ‐ANDCL enables cross‐scale structural orchestration, wherein the atomic‐scale axial N‐bridged sublayer steers cross‐layer charge transfer and triggers Fe d z 2 ‐O 2 p orbitals rehybridization, thereby elevating electron occupancy of antibonding states to weaken *OH adsorption, while the hollow carbon framework ameliorates O 2 diffusion resistance and streamlines transport pathways to achieve efficient mass‐transport. The unique configuration endows FeN 5 ‐ANDCL with exceptional ORR activity, attaining a high half‐wave potential of 0.927 V vs. RHE in alkaline media. When deployed in zinc‐air batteries, it delivers a peak power density of 307.3 mW cm −2 and remarkable cycling stability sustained for 1400 h. Collectively, this work establishes sublayer engineering for precise coordination regulation of single‐atom catalysts and demonstrates a cross‐scale orchestration principle that couples local electronic‐structure optimization with macroscopic transport regulation for efficient electrocatalysis.