Enhanced electrochemical performance of copper vanadate nanorods as an electrode material for pseudocapacitor application

Copper vanadate nanorods were synthesized by simple chemical route and its electrochemical performances were investigated. X-ray diffraction and Fourier transform infrared spectroscopy analyses showed that the copper vanadate nanorods were composed of nano monoclinic crystalline structure having Cu3V2O8 phase with metallic bond vibrations. Observations from scanning electron microscopic and high-resolution transmission electron microscopic studies revealed the rod like morphology of copper vanadate with ~ 200 nm size. Pseudocapacitive behaviour possessed by pristine Cu3V2O8 nanorods was investigated by electrochemical analyses such as cyclic voltammetry, chronopotentiometry and electrochemical impedance spectroscopic techniques using aqueous alkaline electrolyte. Elemental composition with overall atomic distribution was elucidated by energy dispersive spectroscopy combined with elemental mapping. Based on the results, Cu3V2O8 nanorods was proved to be a promising electrode material for pseudocapacitors, as it delivered eminent specific capacitances of 430 Fg−1 at the current density of 0.4 mAcm−2, and 497 Fg−1 at the scan rate of 5 mVs−1. It possesses reasonable cycling stability of 94.7% capacitance retention and superior coulombic efficiency after 5000 charge–discharge cycles at 4 Ag−1.