Two-dimensional hollow carbon skeleton decorated with ultrafine Co₃O₄ nanoparticles for enhanced lithium storage

Transition metal oxides have shown high theoretical capacities as anode materials and have been considered as high potential materials to substitute graphite for composing new generations of lithium-ion batteries (LIBs). However, the considerable volume changes of transition metal oxide materials during practical processes have limited their applications. Herein, we report a simple approach to construct a two-dimensional (2D) hollow carbon skeleton decorated with ultrafine Co₃O₄ nanoparticles (Co₃O₄/C). This composite is derived from a leaf-like zeolitic imidazolate framework-L (ZIF-L (Co)) via etching coordination using tannic acid (TA). The Co₃O₄/C has a unique structure consisting of 2D carbon skeleton, ultrafine Co₃O₄ nanoparticle, and open channel, which can accelerate electron transport, alleviate volume change, and facilitate ion diffusion. Benefiting from these features, the LIBs assembled using Co₃O₄/C as anode material exhibits superior reversible cycle performance and impressive rate property. This study provides an efficient strategy for implementing transition metal oxide-based composites for energy storage applications.