Table of Contents
Smart Materials Research
Volume 2014, Article ID 151732, 9 pages
Research Article

Enhanced Colouration Efficiency of Pulsed DC Magnetron Sputtered WO3 Films Cycled in H2SO4 Electrolyte Solution

1Department of Physics, Alagappa University, Karaikudi 630 004, India
2Directorate of Distance Education, Alagappa University, Karaikudi 630 004, India
3Department of Physics, Alagappa Chettiar College of Engineering and Technology, Karaikudi 630 004, India

Received 15 December 2013; Accepted 15 June 2014; Published 1 July 2014

Academic Editor: Chris Bowen

Copyright © 2014 K. Punitha et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


In the present investigation, we report on DC power and pulsing frequency induced changes in electrochromic properties of pulsed DC magnetron sputtered WO3 films by intercalating/deintercalating H+ ions from 0.1 M H2SO4 electrolyte solution. The observed efficient colouration bleaching mechanism of WO3 films confirms the effective electrochromic nature of the films associated with the electrochemical intercalation/deintercalation of H+ ions and electrons into WO3 lattice. The higher optical modulation was observed in the visible region of the optical transmittance spectra of colored and bleached WO3 films. The maximum coloration efficiency of 79 cm2/C was observed the first time for the film deposited at a DC power of 150 W and a pulsing frequency of 25 kHz.