Thickness-dependent Electrochromic Properties of Amorphous Tungsten Trioxide Thin Films

• Published in: Journal of Nano- and Electronic Physics Vol. 9; no. 3
• Main Authors: Patel, K J, Bhatt, G G, Patel, S S, Desai, R R, Ray, J R, Panchal, C J, Suryavanshi, Priya, Kheraj, V A, Opanasyuk, A S
• Format: Journal Article
• Language: Russian; Ukrainian
• Published: Sumy Ukraine Sumy State University, Journal of Nano - and Electronic Physics 01.01.2017
• Subjects: Bleaching; Composition; Diffusion coefficient; Electrochromism; Film thickness; Glass substrates; Indium tin oxides; Properties (attributes); Thin films; Tin oxides; Tungsten oxides
• ISSN: 2077-6772; 2306-4277
• DOI: 10.21272/jnep.9(3).03040

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.