In this study, we report a facile and simple approach to synthesize a composite of mesoporous NiO nanowires and graphene nanosheets for supercapacitor applications. A Ni precursor was prepared by a one-pot sol-gel method in a water/ethylene glycol mixture containing a graphene oxide. Heat treatment in air was carried out to thermally reduce the graphene oxide to graphene and to convert the Ni precursor to NiO. NiO nanowires possess a rough surface, have a diameter of around 60 nm and are homogeneously deposited on the graphene sheets. The NiO/graphene nanocomposite demonstrates superior pseudocapacitive properties (high specific capacitance, good cyclic performance, and excellent discharge rate capability) as compared to its counterparts. We postulated that this phenomenon arose from the synergistic effect of the addition of graphene as elastic conductive channels, which resulted in better charge transport and more favorable ionic diffusion.

Molybdenum and cobalt binary oxide (CoMoO4) nanowires, nanorods and micro-rhombohedra were synthesized by facile hydrothermal/solvothermal methods.

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In this study, three-dimensional cobalt oxide microstructures were developed. Cobalt oxide microdumbbells and microspheres, assembled by nanowires and primary particles, were successfully synthesized by a multistep hydrothermal method. Of all of the structures, the cobalt oxide microdumbbell electrode possesses the largest surface area of 70.8 m(2) g(-1) and the highest specific capacitance of 407.5 F g(-1). The as-prepared electrode also demonstrates excellent electrochemical stability and retains 97.5% of the initial capacitance after 2000 charge-discharge cycles. This performance is attributed to the desirable morphology, uniform microarchitecture stability, and high surface area. The results show that the as-fabricated Co3O4 is a promising electrode material for supercapacitor applications.