Star-shaped ZIF-derived carbon-based electrocatalysts with FeNX active sites for enhanced oxygen reduction reaction in high-performance zinc-air batteries

A star-shaped Oxygen reduction reaction (ORR) catalyst, Fe-NSC-2, with the growth of carbon nanotubes is prepared. Nitrogen-rich iron phthalocyanine (FePc) is successfully doped into a zeolite imidazolate framework (ZIF-8) by the grinding and pyrolysis methods. Doping FePc into ZIF-8, utilizing its nitrogen ligands and macrocyclic structure, enhances metal dispersion and reinforces the metal-nitrogen (Fe-N X ) configuration. Additionally, this arrangement promotes the graphitization of the three-dimensional porous carbon following pyrolysis. Unexpectedly, the synthesized Fe-NSC-2 catalyst is found to exhibit excellent ORR electrocatalytic activity in alkaline solutions compared to Pt/C. The Zinc-air batteries (ZAB), in which Fe-NSC-2 is employed as the air cathode, is found to exhibit remarkable performance and stability. This provides an economically viable preparation strategy for exploring efficient catalysts for the ORR.