Convenient and large-scale synthesis of hollow graphene-like nanocages for electrochemical supercapacitor application

Hollow graphene-like nanocages are prepared by an efficient and scalable quasi chemical vapor deposition technique. The structure and morphology of the product are investigated by X-ray diffraction, Raman spectrum, scanning electron microscopy, transmission electron microscopy, X-ray photoelectric spectroscopy and nitrogen adsorption-desorption analysis. The supercapacitive performances for the electrode are investigated by cyclic voltammetry and charging-discharging methods. The hollow graphene-like nanocages have a near hollow sphere morphology and nanoporous frameworks. When evaluated for supercapacitor electrode, relatively high specific capacitance of 165.7 F/g and 283.1 F/g are obtained at current density of 1 A/g in 1 M KOH and 1 M H2SO4 electrolytes, respectively. In addition, desirable rate performance and good cycling stability are also demonstrated for the hollow graphene-like nanocages.