Cobalt oxide-graphene nanocomposite as anode materials for lithium-ion batteries.

Composites of CoO/graphene nanosheets are prepared and characterized by X-ray diffraction and scanning electron microscopy. Their electrochemical behavior as anode materials of lithium-ion rechargeable batteries is investigated by galvanostatic discharge/charge measurements and cyclic voltammetry. The composite is composed of CoO nanorods (around 20-40 nm in diameter) and nanoparticles (around 10 nm in diameter) distributed within the graphene matrix. The specific capacity of the composite is higher than both CoO and graphene nanosheets. The cycling stability of CoO is obviously enhanced by compositing with graphene. After 100 cycles, the discharge and charge capacity of the composite is 1,005 and 975 mAh g, respectively, and the irreversible capacity loss is less than 3%. [ABSTRACT FROM AUTHOR]