In this work a new wet-chemical method of preparing tungsten oxide thin films is described. This involves the dissolution of tungsten metal in aqueous hydrogen peroxide and reaction with acetic acid to form an alcohol-soluble precursor. All synthesis stages of this new precursor, termed peroxotungstic ethoxide, are characterized to determine possible reactions. The chemical and microstructural evolution of films is described as a function of firing temperature, utilizing infrared spectroscopy, diffraction and other optical data. A novel method of increasing the crack-free thickness of the films is given: a combination of oxalic acid dihydrate as a solution additive and film firing under controlled humidity. With this combination, fired crack-free films up to one micron in thickness were prepared. Oxalic acid dihydrate roughened and also caused crystallization of these films at lower temperatures (250°C) than expected. These rougher films exhibited an improved electrochromic response, as measured by optical and electrochemical characterizations.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/278554 |
| Date | January 1996 |
| Creators | Kennedy, Steven Roger, 1971- |
| Contributors | Cronin, John P., Zelinski, Brian J. J. |
| Publisher | The University of Arizona. |
| Source Sets | University of Arizona |
| Language | en_US |
| Detected Language | English |
| Type | text, Thesis-Reproduction (electronic) |
| Rights | Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. |
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