Accession Number : ADP006439

Title :   Electrochromic Properties of Sol-Gel Derived WO3 Coatings,

Corporate Author : PARIS-6 UNIV (FRANCE) LAB DE CHIMIE DE LA MATIERE CONDENSEE

Personal Author(s) : Judeinstein, P. ; Livage, J.

Report Date : MAR 1992

Pagination or Media Count : 8

Abstract : Amorphous tungsten oxide layers are deposited via the sol-gel route. Aqueous solutions of tungstate salts (Na2WO4) or chloroalkoxides (WOC12(OPri)2) provide cheap and suitable precursors for the synthesis of W03, nH20 colloidal solutions. Layers of large area can be deposited by spray or dip-coating. They exhibit electrochromic properties and could be used for making display devices or smart windows. Their electrochromic properties depend on the structure of the oxide network and the amount of water of the W03, nH20 layers. Switching time and stability decrease when n increases due to faster ion diffusion. Optical absorption arising from electron delocalization varies with the crystalline structure of the oxide network. Both the structure and the hydration state of the layers depend on the experimental procedure. It is therefore possible to optimize the electrochromic properties of sol-gel derived layers.

Descriptors :   *GELS, *TUNGSTEN OXIDES, *OPTICS, ABSORPTION, COATINGS, DIFFUSION, DIP COATING, ELECTRONS, HYDRATION, IONS, LAYERS, NETWORKS, OXIDES, PRECURSORS, SPRAYS, STABILITY, STRUCTURES, SWITCHING, SYNTHESIS, TIME, TUNGSTATES, TUNGSTEN, WATER, WINDOWS.

Subject Categories : Optics
      Inorganic Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE