Thickness-dependent Electrochromic Properties of Amorphous Tungsten Trioxide Thin Films

Author(s) K.J. Patel1 , G.G. Bhatt1 , S.S. Patel2, R.R. Desai2, J.R. Ray3, C.J. Panchal4 , Priya Suryavanshi4, V.A. Kheraj5, A.S. Opanasyuk6

1 BITS Edu Campus, Varnama, Vadodara, Gujarat, India

2 Sardar Patel University, Vallabh Vidyanagar-388120, Gujarat, India

3 H. V. H. P. Institute of P.G. Studies and Research, Kadi Sarva Vishwavidyalaya, Kadi, Gujarat, India

4 The M. S. University of Baroda, Vadodara-390001, India

5 S. V. National Institute of Technology, Surat 395007, India

6 Sumy State University, 2, Rymskyi-Korsakov Str., 40007 Sumy, Ukraine

Issue Volume 9, Year 2017, Number 3
Dates Received 28 April 2017; revised manuscript received 04 May 2017; published online 30 June 2017
Citation K.J. Patel, G.G. Bhatt, S.S. Patel, et al., J. Nano- Electron. Phys. 9 No 3, 03040 (2017)
DOI 10.21272/jnep.9(3).03040
PACS Number(s) 73.61.Jc, 78.20.Jq
Key words Electrochromic (4) , Thermal evaporation (8) , Tungsten trioxide.
Annotation Tungsten Trioxide (WO3) thin films were grown by thermal evaporation method to study the effect of film’s thickness on its electrochromic (EC) properties. The WO3 thin films of different thicknesses were grown on Indium Tin Oxide (ITO) coated glass and soda lime (bare) glass substrate held at room temperature. The surface composition of the thin films was investigated using X-ray photoelectron spectroscopy measurement, which showed the oxygen to tungsten atomic composition ratio to be nearly 2.97. The EC properties of the thin films were examined using electrochemical techniques. Cyclic-voltammetery shows the diffusion coefficient (D) of the intercalated H+ ion in the WO3 thin film increases with the film’s thickness. It turns out that the ‘thicker’ film exhibits better coloration efficiency (CE) as compared to the ‘thinner’ film. The coloration time was found to be independent of film thickness; however, the bleaching time increases as the film thickness increases.