Cobalt Oxide Modified Reduced Graphene Oxide Nanocomposite as Anode Materials for Lithium-Ion Batteries

In this paper, Co3O4 nanoparticles and Co3O4 modified reduced graphene oxide (Co3O4/rGO) are successfully elaborated by hydrothermal method and used as anode materials in lithium-ion batteries. The structure, composition, and morphology of the hydrothermal powders are characterized by XRD, Raman spectroscopy, SEM, and TEM while their electrochemical performance was evaluated using cyclic voltammetry and galvanostatic charge/discharge studies. The Co3O4/rGO anode exhibit improved electrochemical performance in terms of specific capacity, reversibility and stability compared to single-component Co3O4. At 0.1 A g(-1), the specific charge/discharge capacity for the pure Co3O4 is 855 mAh g(-1) and 850 mAh g(-1) respectively, while for Co3O4/rGO composite is about 1198 mAh g(-1) and 1285 mAh g(-1) respectively. It is found that the conductivity values increase with adding of the rGO from 4.4 x 10(-4) ohm cm for the Co3O4 to 4.5 x 10(5) ohm cm for Co3O4/rGO composite. The improvement in the electrochemical capacity of the composite anode is mainly ascribed to a cooperative effect between the rGO with good electrical conductivity and the unique nano-sized Co3O4 with a short diffusion pathway for lithium ions diffusion.