Atomically dispersed single Co sites on S, N-codoped porous carbon as efficient oxygen reduction reaction electrocatalyst for zinc-air batteries

Background The development of efficient and durable oxygen reduction reaction (ORR) catalysts plays a vital role in promoting the development of metal-air batteries (MABs). Methods Herein, a Co single-atom catalyst ( f -Co@SNC) supported on a flower-like S, N-codoped porous carbon substrate was prepared using a polydopamine-coated dual-linker zeolitic tetrazolate framework (ZTF) as a precursor. The polydopamine coating and 2-methylimidazole linker are used as structural stabilizers and provide nitrogen and carbon sources, while the thermally unstable and high-energy linker (5-aminotetrazole) and in-situ embedded thiourea guest serve as sacrificial templates to create abundant of S, N-codoped sites and well-developed porous structures. Significant Findings Benefiting from the high-density atomically dispersed single Co sites and structure advantages, the optimized f -Co@SNC catalyst exhibits excellent ORR catalytic performance with half-wave potential of 0.871 V and excellent catalytic stability over 10 h, even surpassing commercial Pt/C catalyst. Impressively, rechargeable zinc-air battery (ZAB) using f -Co@SNC as the air cathode catalyst exhibit a desired peak power density of 118.5 mW cm −2 , energy density of 794.6mAh g Zn −1 and an excellent charge-discharge cycle stability over 145 h. This work presents a facile method for preparing SACs for efficient ORR, which will provide meaningful guidance for promoting the development of next-generation clean energy conversion devices.