Preparation of Co₃O₄/Carbon Derived from Ionic Liquid and Its Application in Lithium-ion Batteries

In this paper, we report an ionic liquid derived Co₃O₄/Carbon (Co₃O₄/C) material synthesized by a carbothermic reduction followed by a low-temperature oxidation, which is certified by XRD and TEM. The as-synthesized Co₃O₄/C composite has a uniform structure with well-crystalized Co₃O₄ embedded in carbon matrix (onion-like carbon materials). The carbon held tightly on the Co₃O₄ particles can prevent the disintegration of Co₃O₄/C composite during cycling and, therefore, improve the integrity of the composite. Moreover, the carbon component of the composite can enhance the dynamic characteristic of the Co₃O₄/C composite, which can accelerate the electronic conductivity. The composite delivers excellent lithium storage performances with outstanding cycling performance (868 and 877 mAh g⁻¹ after 200 cycles at a current density of 89 mAh g⁻¹) and admirable rate capability (660 and 669 mAh g⁻¹ at a rate of 2C) in lithium-ion batteries (LIBs), showing great prospect as electrode material for LIBs.