Bulk to nanostructured vanadium pentaoxide-nanowires (V_2O_5-NWs) for high energy density supercapacitors

摘要

Vanadium pentoxide (V_2O_5) has attracted huge attention in field of energy storage including supercapacitor electrodes due to its low cost and layered structure. In this present study, Bulk V_2O_5 has been prepared by the calcination of ammonium metavanadate followed by the synthesis of V_2O_5-nanowires (V_2O_5-NWs) by hydrothermal treatment of bulk V_2O_5. Obtained V_2O_5-NWs was further used to fabricate the supercapacitor electrodes. Structure and morphology analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). Energy storage capability of as prepared nanowires was investigated by Galvanostatic charge-discharge (GCD), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in aqueous electrolyte (1M H2SO4). High specific capacitantance of about 622 F/g was achieved at 1 A/g. Along with high storage by faradic charge storage mechanism; V_2O_5-NWs electrodes also possess high stability. It could retain 63% of its initial capacitance even after 1000 GCD cycles. Excellent performance of V_2O_5-NWs promotes its commercial utilization for the development of high performance supercapacitors.