Fabrication of NiO Nanowires/G Composite as Electrode Material for High Performance Supercapacitor

Abstract

Layer structure of graphene explores wide potential for the development of novel electrochemical materials. In this paper, NiO nanowires/G composite (NOG) was fabricated by synthesis of NiO nanowires (NWs) from nickel carbonates basic nanosheets anchored onto G sheets. NiO NWs were dispersed onto the surface of G sheets homogeneously. The layer structure of G sheets was maintained in NOG. The as-prepared composite is characterized using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Thermogravimetric analysis(TG), Transmission electron microscope(TEM), High Resolution Transmission Electron Microscopy(HRTEM) and X-ray photoelectron spectrum (XPS). NOG was employed as electrode active material for super capacitor. Excellent performances were obtained with high specific capacity up to 351 F g-1 at current density of 2 A g-1 in the initial cycle. A capacitance retention of 94.2 % can be maintained after 1000 cycles. With high charging-discharging current density up to 20 A g-1, a high capacitor of 214.5 F g-1 still can be achieved, suggesting its promising potential in supercapacitors. The improved structure stability and electron conductivity of NOG should be responsible for the capacitance properties.