Room-temperature synthesis of CuO/graphene nanocomposite electrodes for high lithium storage capacity

A facile approach for the synthesis of hybrid nanocomposite electrodes comprising pine-nut-shaped cupric oxide (CuO) particles and electrolytically exfoliated conducting graphene nanosheets (GNSs) for lithium ion battery applications is demonstrated. The GNSs were initially dispersed in aqueous solution, and then, Cu(OH)2 was synthesized by the reaction of CuSO4·5H2O, NH4OH, and NaOH. In the subsequent chemical reduction process, a controlled amount of hydrazine hydrate (N2H4·H2O) was added to the reaction mixture to obtain the CuO/GNS nanocomposite. Information about the phase, surface properties, and morphology of the CuO and CuO/GNS composite was obtained by X-ray diffraction, Brunauer–Emmett–Teller surface analysis, field-emission scanning electron microscopy, and high-resolution transmission electron microcopy. The electrochemical performance of the nanocomposite was evaluated by cyclic voltammetry and galvanostatic cycling. The nanocomposite synthesized by this method had a uniform morphology without aggregation and showed enhanced electrochemical performances.