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

  • Anoop Agrawal
  • John P. Cronin
Part of the Advances in Sol-Gel Derived Materials and Technologies book series (Adv.Sol-Gel Deriv. Materials Technol.)


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 sol-gel 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.


Bleached state Dip coating Electrochromic Fluorine-doped tin oxide Indium tin oxide Insulated glass unit Intercalation Physical vapor deposition (PVD) Plasma enhanced chemical vapor deposition (PECVD) Reversible electrochemical devices Sputtering Switchable devices Tungsten oxide WO3 film 

List of abbreviations




Insulated glass unit


Fluorine doped tin oxide


Indium tin oxide


American society for testing materials


User controlled photochromic devices


Physical vapor deposition


Plasma enhanced chemical vapor deposition


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Copyright information

© © Springer Science+Business Media New York 2012

Authors and Affiliations

  1. 1.AJJER LLCTucsonUSA

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