A facile hydrothermal synthesis of tungsten doped monoclinic vanadium dioxide with B phase for supercapacitor electrode with pseudocapacitance

Abstract

Tungsten doped monoclinic vanadium dioxide with B phase (W-doped VO2(B)) was successfully synthesized by a facile hydrothermal route. The composition, structure and morphology were characterized by EDS, element mapping, XRD, XRF and TEM. The results showed that W atom was successfully doped into the crystal lattice of VO2(B) matrix, and the homogeneous solid-solutions of W-doped VO2(B) nanobelts were prepared. The electrochemical properties of W-doped VO2(B) nanobelts as a supercapacitor electrode were investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) methods. W-doped VO2(B) nanobelts displayed excellent pseudocapacitance property and their specific capacitance were 253, 239, 207, 164 and 148Fg−1 at the current density of 1, 2, 5, 10 and 20Ag−1, respectively. They also exhibited excellent energy densities of 323, 305, 265, 209 and 189Whkg−1 at power densities of 2882, 5758, 14,433, 28,828 and 57,661Wkg−1. The results showed the electrochemical performance of VO2(B) can be greatly improved by W-doped VO2(B).