Temperature dependent surface morphological modifications of hexagonal WO3 thin films for high performance supercapacitor application

In present article, temperature dependent surface morphological modification and its subsequent influence on electrochemical performance of hexagonal WO3 (h-WO3) thin films has been investigated. The nanostructured h-WO3 films are synthesized on carbon cloth substrate using simple hydrothermal method. It is observed that h-WO3 thin films prepared at temperature of 413, 433 and 453 K display nanogranule-like, nanoplate-like and nanorod-like suface morphology. The X-ray diffraction study discloses the prominent orientation along (001) and (200) planes which reveals the preferential growth direction of h-WO3 along c and a-axis, respectively. The h-WO3 film prepared at 453 K shows good surface area, pore volume and uniform pore size distribution. The electrochemical measurements exhibit high specific capacitance of 694 F g−1, energy density of 25 Wh Kg−1 and long term cycling performance (87 % capacitance retention after 2,000 cycles) for h-WO3 thin film. The results indicate that h-WO3 nanorods could be a promising electrode material for high performance energy storage devices.