The Merits of Sol-Gel Processing for Electrochromic Windows: A Commercial Perspective

Abstract

Electrochromic windows are reversible electrochemical devices. For architectural windows, typical electrochromic device structures comprise of several layers of coatings, where oxidation and reduction of electrode coatings result in actively controllable optical properties by application of electrical potential. These windows reduce the energy cost of a building envelope by dynamically changing the solar transmission through the windows which are used to optimize both the lighting costs and thermal gains with changing outdoor conditions. Commercial electrochromic windows are now becoming available; however, to obtain broader market acceptance the cost/benefit ratio of these windows must be improved. The windows being introduced into the marketplace do not use sol-gel technology in their manufacturing process. Judicious use of solgel technology can assist in obtaining a more favorable cost/benefit ratio. Sol-gel processes offer the opportunity of making the cost attractive, given the unique aspects of the coatings used in this application, which include multiple metal oxide compositions, significant thickness, microstructural requirements, incorporation of mobile ions and the ability to effectively use low-cost transparent conductors.

Optical and Physical Properties of Methyltrimethoxysilane Transparent Film Incorporated with Nanoparticles

“…One way to prepare the coatings is the sol-gel process. It is a simple technique and has been used to produce film with high optical transparency [4] and low thermal conductivity [5] and presently widely used in architectural window [6][7][8]. Due to its simplicity, sol-gel coatings are widely used in those related with optical semiconductor [9], protective [10][11][12], and sensing application [13].…”