Porous Core–Shell Co₃O₄@CuCo₂O₄ Derived from Metal–Organic Frameworks as the Cathode Material for Lithium–Oxygen Batteries

Nonaqueous lithium-oxygen (Li-O2) batteries, owing to their ultrahigh theoretical energy density, have attracted extensive research attention. However, the commercialization of these systems is limited by the sluggish kinetics, necessitating advanced catalyst design. Herein, ZIF-67 is utilized as a self-sacrificial template to fabricate dual spinel Co3O4@CuCo2O4 with a porous core-shell structure via a simple solvothermal-calcination process, which is designed as a highly efficient cathode electrocatalyst for the Li-O2 battery. The unique porous core-shell nanostructure provides abundant accessible interfacial area and high pore volume, enabling efficient oxygen diffusion and electron transfer, which collectively enhance the catalytic activity. Electrochemical tests have revealed that the Li-O2 battery with a Co3O4@CuCo2O4 based cathode exhibits exceptional performance, such as a large initial discharge capacity of 7015.5 mAh g-1 at 100 mA g-1, prime cyclability of 146 times at 400 mA g-1 under a capacity limitation of 1000 mAh g-1, and a low initial overpotential of 1.47 V at 500 mA g-1. This work proposes a general strategy for optimizing the composition-structure relationship of advanced electrocatalyst in Li-O2 batteries.