<title>Sol-gel deposition of electrochromic copper oxide films</title>

Abstract

This paper discusses the optical and electrochromic properties of Cu_xO films deposited by sol-gel process. UV-VIS-NIR spectroscopy, SEM, X-ray Diffraction and X-ray Photoelectron spectroscopy have been employed in a study of structure and optical properties of coatings. The sol-gel process offers new approaches to optical properties of coatings prepared by the acid catalyzed reactions of alkoxides. Cu_xO polymeric solutions are formed upon hydrolysis-condensation of copper ethoxide. Transparent amorphous Cu_xO coatings ranging in the thickness from 43 to 615 nm, were deposited on Corning 7059 and transparent conducting plates from polymeric solutions. These films exhibited reversible electrochromism that their color turn from transparent to pale brown. The combined effect of firing temperature (in the range of 70 - 450 degree(s)C) on optical properties and response time of these films are investigated. Significant changes in optical properties and electrochromic properties have been observed with firing temperatures.