Low-Loading Fe Single-Atom Sites Ordered Honeycomb-Structured Carbon-Based Catalyst for High-Performance Flexible Zinc-Air Batteries

Non-noble metal single-atom catalysts (SACs) have emerged as promising alternatives to Pt-based catalysts for the oxygen reduction reaction (ORR) due to their high atomic utilization and low cost. Nevertheless, the facile aggregation of metal atoms during synthesis severely reduces the density of active sites, thereby restricting their practical application in metal-air batteries. Herein, we fabricated a highly dispersed Fe single-atom catalyst (Fe-N-C) anchored on honeycomb-structured carbon (HCC). The synergistic effect of low iron content, physical confinement of honeycomb carbon, and chemical anchoring of nitrogen sites effectively inhibits metal atom aggregation and maximizes the atomic dispersion of Fe active sites. Benefiting from the ordered honeycomb porous structure and high atomic utilization, the as-synthesized Fe-N-C exhibits an outstanding half-wave potential of 0.875 V even at a low Fe loading. Notably, when applied as the air cathode in a flexible solid-state zinc-air battery, this catalyst delivers a peak power density of 160.7 mW cm − 2 , outperforming most reported non-noble metal ORR catalysts to date. This work provides a feasible strategy for the fabrication of highly dispersed single-atom catalysts for high-performance flexible energy conversion devices. Graphical The alternative text for this image may have been generated using AI.