1. Electrochromic Nb-doped WO3 films: Effects of post annealing
- Author
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Wang, Chun-Kai, Sahu, Diptiranjan, Wang, Sheng-Chang, and Huang, Jow-Lay
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ELECTRIC properties of metallic films , *TUNGSTEN oxides , *NIOBIUM , *METALLIC oxides , *ANNEALING of metals , *CERAMIC metals , *ELECTRON beams , *EVAPORATION (Chemistry) - Abstract
Abstract: The Nb-doped WO3 films were deposited by e-beam co-evaporation method using ceramic WO3 targets and metal Nb slugs. The films were analyzed by glancing incident angle X-ray diffraction (GIAXRD), UV/visible spectrophotometer, electrochemical cyclic voltammetry, X-ray photoelectron spectroscopy (XPS). The as-prepared film is brown and amorphous in structure. The film has low transmission in optical visible region. The XPS results indicate that the as-deposited film is non-stoichiometric. By applying a negative potential, the as-deposited film does not show obvious electrochromic effect. However, the electrochromic properties of Nb-doped WO3 films are improved by post annealing treatment at 350, 400, and 450°C in oxygen atmosphere. The Nb-doped WO3 films transform into crystalline structure and become transparent after post annealing treatment. The energy band gap, optical modulation, and color efficiency increase with annealing temperature. [Copyright &y& Elsevier]
- Published
- 2012
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