Fast coloration in sputtered gasochromic tungsten oxide films

Thin films of WO3 were deposited with different thickness in a mixed atmosphere of O2 and Ar gas from a high purity target of 99.99% tungsten using reactive DC-sputtering technique. Same amount of the Pt catalyst was sputtered from a high purity target of 99.99% platinum in Ar atmosphere onto the top of the WO3 films with different thickness. Coloration takes place in hydrogen and bleaching in oxygen gases. During the coloration/bleaching process several optical parameters were determined. The velocity of coloration process increases with increasing the thickness of the films. The change of the transmission in the visible and near infrared regions was measured during coloration and bleaching process. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)