Paper Title
Study of Gasochromic Hydrogen Sensing Properties of Nanostructured PT/WO3 Thin Films Prepared by Sol-Gel Method

Abstract
Metal Oxide-based Chemi-resistive sensors for hydrogen gas detection utilize microheaters, posing a risk of explosion due to electric sparks, as hydrogen concentrations above 4% are highly flammable. Gasochromic sensors, on the other hand, are safe as they can detect target gas based on changes in optical transmittance at room temperature. The transmittance of the gasochromic tungsten oxide films changes reversibly in the presence and absence of the target gas. In this work, Pt-doped nanostructured WO3 thin films are prepared by the sol-gel spin coating method. UV-VIS-NIR transmittance spectra of the samples were recorded at room temperature by alternatively exposing the samples to 4% Hydrogen and synthetic air. The results show that gasochromic sensing can be enhanced by increasing the doping concentration to 2wt%. The better sensing could be attributed to the fine dispersion of the Pt nanoparticles on WO3 thin films facilitating the adsorption and hydrogenation of molecular hydrogen. Keywords - Hydrogen Sensors, Gasochromic, Sol-Gel, WO3 Thin Film