| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1686650 | Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms | 2007 | 4 Pages |
The effects of composition and structure on gasochromic coloration of tungsten oxide films for hydrogen have been investigated. Tungsten oxide films with various O/W atomic ratios from 1.5 to 3.0 are prepared using a reactive rf magnetron sputtering from a tungsten target at different oxygen partial pressures. The films were deposited on quartz and carbon substrates at 200 °C. The O/W atomic ratio and crystallographic structure of the films were determined by Rutherford backscattering spectroscopy and X-ray diffraction. The gasochromic properties of the films were examined by use of optical transmittance in exposure in 1% H2/Ar atmosphere. The stoichiometric WO3 film with amorphous structure resulted in superior gasochromic coloration. The decrease in gasochromic performance was caused by non-stoichiometric WO3 films with amorphous structure or stoichiometric WO3 films crystallized with post-annealing at temperatures higher than 300 °C in air. It suggests that the gasochromic coloration of tungsten oxide films for hydrogen is strongly influenced by the composition and structure.
