Fabrication Based on the Kirkendall Effect of Co₃O₄ Porous Nanocages with Extraordinarily High Capacity for Lithium Storage

Abstract Herein we report a novel facile strategy for the fabrication of Co 3 O 4 porous nanocages based on the Kirkendall effect, which involves the thermal decomposition of Prussian blue analogue (PBA) Co 3 [Co(CN) 6 ] 2 truncated nanocubes at 400 °C. Owing to the volume loss and release of internally generated CO 2 and N x O y in the process of interdiffusion, Co 3 O 4 nanocages with porous shells and containing nanoparticles were finally obtained. When evaluated as electrode materials for lithium‐ion batteries, the as‐prepared Co 3 O 4 porous nanocages displayed superior battery performance. Most importantly, capacities of up to 1465 mA h g −1 are attained after 50 cycles at a current density of 300 mA g −1 . Moreover, this simple synthetic strategy is potentially competitive for scaling‐up industrial production.