Structural and optical properties of WO3 electrochromic layers prepared by the sol-gel method

• Authors: Abdoljavad Novinrooz , Masoomeh Sharbatdaran , Hassan Noorkojouri
• Languages of publication: EN

Abstracts

EN

Thin layers of tungsten trioxide have been prepared from an aqueous solution of peroxotungstic acid (PTA) using the sol-gel method. Compositional, structural and optical characteristics of WO3 coated on indium tin oxide (ITO) conductive glass substrates were studied using X-ray diffractometery (XRD), cyclic voltammetery (CV), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Monoclinic and triclinic crystalline structures for thin film and powdered WO3 were confirmed by XRD analysis. SEM micrograph of annealed samples revealed micro cracks due to a decrease in density and a contraction of layers. EDX analysis showed that 1∶2 ratio of oxygen and tungsten atoms in the prepared films is obtained at heat treatment temperatures higher than 200 °C. Furthermore, the annealed samples showed very good electrochromic behavior in cyclic voltammetery studies. Refractive index “n” and extinction coefficient “k” values were found to be reduced by increasing the wavelength and decreasing the temperature.

Keywords

EN

Sol-gel; tungsten oxide; thin film; electrochromic; structural and optical properties; 78.20.jq; 81.15.-z; 81.20.Fw; 78.66.-w

• Publisher: De Gruyter Open
• Journal: Open Physics
• Year: 2005
• Volume: 3
• Issue: 3
• Pages: 456-466

Dates

published

1 - 9 - 2005

online

1 - 9 - 2005

Contributors

author

Abdoljavad Novinrooz

• Material and Ion Beam Application Division, Nuclear Research Center for Agriculture and Medicine, Atomic Energy Organization of Iran (AEOI), P.O. Box, 31485-498, Karaj, Iran

author

Masoomeh Sharbatdaran

• Material and Ion Beam Application Division, Nuclear Research Center for Agriculture and Medicine, Atomic Energy Organization of Iran (AEOI), P.O. Box, 31485-498, Karaj, Iran

author

Hassan Noorkojouri

• Material and Ion Beam Application Division, Nuclear Research Center for Agriculture and Medicine, Atomic Energy Organization of Iran (AEOI), P.O. Box, 31485-498, Karaj, Iran

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Identifiers

DOI

10.2478/BF02475650