Improvement of hydrogen gas sensing property of the sol–gel derived Pt/WO₃ thin film by Ti-doping

Abstract

Platinum nano particles dispersed tungsten trioxide (Pt/WO 3 ) is a promising hydrogen gas sensor material which can detect it by the change of color. Hydrogen gas sensing properties of Pt/WO 3 thin film strongly depend on its film structure. Particularly, the porosity and the particle size of WO 3 are very important for obtaining good hydrogen sensitivity. The morphology of Pt/WO 3 thin film prepared by solgel process can be modified by the heat-treatment temperature and the Ti-doping to WO 3 . Pt/WO 3 thin films consisting of small particles and porous structure were obtained by Ti-doping. Especially, Ti-doping was very effective to obtain the small WO 3 particle in spite of a high temperature heat treatment. It was considered that Ti-doping produced oxygen vacancy in WO 3 lattice and this disturbed the densification of the film and the grain growth of WO 3 . This sample showed a good response to hydrogen gas exposure, compared with that of non-doped sample. Therefore, it was found that the surface modification by Ti-doping can enhance the optical hydrogen gas sensing property of Pt/WO 3 .

Pt/WO3 Nanoparticle-Dispersed Polydimethylsiloxane Membranes for Transparent and Flexible Hydrogen Gas Leakage Sensors

“…The particle sizes of WO 3 in the Pt:W = 1:13 and Pt:W = 1:100 powder samples were 41.0 ± 7.2 nm and 46.2 ± 6.3 nm, respectively ( Figure S1 in Supplementary Materials ). These results agree well with our previous report [ 20 ].…”

Optical hydrogen sensing with high-Q guided-mode resonance of Al2O3/WO3/Pd nanostructure

“…To overcome this problem, a higher sensitivity is necessary. Various approaches, including doping and nanostructuring, were used to enhance gasochromic response of WO 3 -based sensors to hydrogen 7 , 18 , 19 . One of the main goals of nanostructuring is the increase of the optical response while keeping the building layers thin to provide a rapid response.…”