Intertwining network structured VnO2n+1-CNT/GO nanocomposite electrodes for supercapacitors

The V3O7 center dot H2O-CNT/GO nanocomposite has been synthesized using facile hydrothermal method by incorporation of functionalized carbon nanotubes (CNTs) and Graphene oxide (GO) with ratio of 1:0.8. The predominant (200) and (520) X-ray diffraction (XRD) peaks corresponds to orthorhombic structure with crystallite size of 21 nm. The Raman spectrum shows the D and G bands along with V5+=O and V4+=O bands of V3O7 center dot H2O signifies the existence of carbonaceous materials such as CNT and GO. The scanning electron microscopy (SEM) and Transmission electron microscopy images confirmed intertwining network structure of V3O7 center dot H2O-CNTs/GO nanocomposite and demonstrated a specific capacitance of 269 F g(-1). Further, the transformation of V3O7 center dot H2O-CNT/GO to V2O5-CNT/GO composite was observed annealing at a temperature of 450 degrees C in oxygen environment. The intertwining network structured V2O5-CNT/GO nanocomposite has gained high mechanical strength from CNTs and high surface area from GO nanosheets along with excellent conductivity and demonstrated a high discharge specific capacitance 1020 F g(-1) and retained 83.9% capacitance even after 5000 cycles.