Hierarchically engineered electrocatalysts for durable oxygen reduction in zinc–air batteries

Rechargeable zinc–air batteries (ZABs) are promising energy storage systems but are limited by sluggish oxygen reduction reaction (ORR) kinetics at the air cathode. Herein, we report hierarchically engineered cobalt tetraaminophthalocyanine/MXene (CoPc/MXene) electrocatalysts prepared via cetyltrimethylammonium bromide‐mediated self‐assembly. The resulting hierarchical architecture suppresses molecular aggregation and promotes O 2 diffusion, OH − transport, and electron conduction, thereby improving three‐phase mass transport and Co–N 4 activity. Concurrently, this interfacial assembly enables Co–Ti coupling that modulates the Co 3d electronic structure, shifts the d‐band center upward, and optimizes ORR intermediate adsorption. Consequently, CoPc/MXene delivers a half‐wave potential of 0.85 V and cycling durability exceeding 1200 h, outperforming the Pt/C+RuO2‐based benchmark. The corresponding ZAB achieves a high power density of 167 mW cm −2 and a specific capacity of 869 mAh g −1 . This work provides a hierarchical interface engineering strategy for durable electrocatalysts in metal–air batteries and related gas‐involving electrochemical systems.