Three-dimensional graphene skeletons supported nickel molybdate nanowire composite as novel ultralight electrode for supercapacitors

Nickel molybdate (NiMoO$_{4}$) nanowires were prepared on chemical-vapor-deposition-grown three-dimensional graphene skeletons by hydrothermal method. The X-ray diffraction and Raman results show that NiMoO$_{4}$ is $\alpha{}$ phase. This binder-free and ultralight graphene/ NiMoO$_{4}$ composite was used as a positive electrode for supercapacitors. This electrode presents a high specific capacitance of 1194 F g$^{-1}$ at 12 mA cm$^{-2}$ and the good stability with a cycling efficiency of 97.3% after 1000 cycles. Further, the energy density reaches an energy density of 41 Wh kg$^{-1}$ at a steady power density of 1319 W kg$^{-1}$. These results demonstrate the potential of the designed composite for the future flexible and lightweight energy storage.