A multi-metal (Fe, Cu, Zn) coordinated hollow porous dodecahedron nanocage catalyst reduces oxygen in Zn-air battery

The coupling of low-cost, multiple metals and porous nanocarbon materials, aimed at replacing precious metals to enhance electrocatalytic oxygen reduction, is a critical challenge to some crucial research. This paper constructed a hollow dodecahedron nanocage catalyst (Fe3O4/CuNCs/ZnNx-PHNC) by supporting copper nanoclusters, Fe3O4 nanoparticles, and Zn-NX after sintering and annealing, using the coordination of ZIF-8 and doping copper and iron ions. We observed that the synergy of the multi-metals in the magnetically separable heterojunction catalyst induced an electron transfer and inhibits hydrogen peroxide formation, thus, improving its catalytic performance for oxygen reduction reaction. Its half-wave potential is as high as 0.832 V, and the Tafel slope is 54 mV/decade, superior to many non-precious metal catalysts in literature. The assembled Zn-air battery (ZAB) exhibits a maximum power density of 162 mW⸱cm-2 and ultra-high stability of >500 h at a 5 mA⸱cm-2 current density. The ZAB’s excellent performance also proves high development and practical application prospects.