| 초록 |
Metal oxide/graphene composites have drawn significant interest for use as an anode in high-performance lithium ion batteries (LIBs). Among various metal oxides, Co3O4 is one of the most promising anode materials in LIBs due to its high theoretical capacity of 890 mAh g-1. In this study, an ex-situ solvothermal synthesis method was employed to accurately control the concentration of Co3O4 nanoparticles (NPs) in the composite, maintaining the uniform size and morphology. Co3O4 NPs, approximately 9 nm in size, were synthesized using a solvothermal method, and Co3O4/graphene composites were then prepared from the Co3O4 NPs and graphene oxide (GO) sheets by a second solvothermal process involving the reduction of GO. The Co3O4/reduced graphene oxide (RGO) composites exhibited the highest reversible capacity of 1600 mAh g−1 at 43 wt.% Co3O4 NPs. The synergic effects of the sub-10-nm sized Co3O4 and the RGO sheets resulted in improved reversible capacity, cycling stability, and rate capability, which are caused by a large number of active sites and the short diffusion pathways provided by the nano-sized Co3O4, as well as the elastic buffer space and conductive pathway provided by the RGO sheets. |
