Amorphous and crystalline WO3films show electrochromic properties by means of double injection of cations and electrons. Absorption by small polaron transitions has been hypothesised to explain the coloration mechanism in amorphous WO3films and the most reliable model was found by Zhang, who proposed that a WO3-xbleached virgin film (x<0.4) consists mainly of W6+and W4+, whereas in the coloured state W5+is also present. In this work, amorphous WO3films have been deposited by a thermal evaporation technique on glass and c-Si substrates. Electrical, optical and IR properties of these samples have been studied. A hopping mechanism with mobility activation has been hypothesised to justify the discrepancies between electrical and optical properties. Furthermore, our careful analysis of the typical IR absorption peaks in the range 500-1000 cm-1confirmed the Zhang theory on the coloration mechanism. © 2002 Elsevier Science B.V. All rights reserved.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry
Antonaia, A., Santoro, M. C., Fameli, G., & Polichetti., T. (2003). Transport mechanism and IR structural characterisation of evaporated amorphous WO. Thin Solid Films, 426(1-2), 281 - 287. https://doi.org/10.1016/S0040-6090(03)00011-7