Symmetry distortion engineering single-atom catalysts: Exceptional ORR activity and ultra-stable Zn-air batteries

Oxygen reduction reaction (ORR) catalysts are crucial components in next-generation energy storage systems, such as high-energy–density Zn-air batteries (ZABs), as they serve as performance-determining process in devices. However, current ORR catalysts still face significant challenges that hinder their practical applications: Pt/C catalysts incur high costs due to reliance on noble metals, while non-noble metal-based systems often struggle with low activity and stability. In this study, a novel non-noble Fe-N 4 single-atom catalyst, FeN4ClPO, coordinated by both an axial Cl ligand and a long-range P-O ligand was designed and synthesized. The high-coordination FeN4ClPO catalyst achieves performance surpassing Pt/C catalysts, with a remarkable half-wave potential (0.903 V), a peak power density of 179.6 mW/cm 2 , and exceptional durability lasting up to 300 h. This performance is driven by our broadly applicable synergistic coordination strategy, which efficiently and precisely tunes regulated the electron density distribution, d -orbital energy levels, and spin state of the Fe center. Moreover, A flexible solid-state ZAB was constructed with the FeN4ClPO catalyst, exhibiting excellent foldability and cycle stability. These findings provide a feasible approach for the design of efficient catalysts in high-energy and high-safety rechargeable batteries.