Nanopore Confinement of Electrocatalysts Optimizing Triple Transport for an Ultrahigh‐Power‐Density Zinc–Air Fuel Cell with Robust Stability

Abstract Metal–air fuel cells with high energy density, eco‐friendliness, and low cost bring significantly high security to future power systems. However, the impending challenges of low power density and high‐current‐density stability limit their widespread applications. In this study, an ultrahigh‐power‐density Zn–air fuel cell with robust stability is highlighted. Benefiting from the water‐resistance effect of the confined nanopores, the highly active cobalt cluster electrocatalysts reside in specific nanopores and possess stable triple‐phase reaction areas, leading to the synergistic optimization of electron conduction, oxygen gas diffusion, and ion transport for electrocatalysis. As a result, the as‐established Zn–air fuel cell shows the best stability under high‐current‐density discharging (>90 h at 100 mA cm −2 ) and superior power density (peak power density: >300 mW cm −2 , specific power: 500 Wg cat −1 ) compared to most reported non‐noble‐metal electrocatalysts. The findings will provide new insights in the rational design of electrocatalysts for advanced metal–air fuel cell systems.