Investigation of optical response of gasochromic thin film structures through modelling of their transmission spectra under presence of organic vapor

Abstract

Properties of chromogenics materials have been of great interest for more than 50 years till now. Some examples of their practical application are photochromic lenses, electrochromic smart windows or even some examples of sensors devices based on gasochromic thin films have already been commercially available on the market. However, recognition of different physical and chemical processes that influence the optical response of such materials under changes in surrounding atmosphere is still an open subject for discussion. This work presents results of experimental and theoretical investigations of optical response of the two selected gasochromic (Ti-V-Ta-W)Ox and (Ti-V-Ta-Nb)Ox oxide thin films under ethanol vapor stimulations. Based on the measured experimental transmission spectra, the complex refraction index characteristics were plotted using optical models elaborated for the VIS-NIR spectral range. The models were further used for the prediction of optical responses of optical gas sensing structures with observed gasochromic behavior.