Thick-film gas sensors based on vanadium–titanium oxide powders prepared by sol-gel synthesis

Abstract

Two titania powders modified by 10 at.% of vanadium were prepared by two different sol-gel routes. The powders fired at 650 C had the rutile structure. These powders were used to produce prototype thick-film sensors. Four series of thick-film samples were fabricated by screen-printing, fired for 1 h at 650 and 850 C. The morphology and gas-sensing properties were examined and compared with those of pure and Ta-added titania films, previously studied by the authors. Ta addition inhibited the anatase-torutile phase transformation during heating and was also effective in keeping the TiO 2 grain size in the nanometre range. On the contrary, V addition facilitated the anatase-to-rutile phase transformation. Thick films obtained from the two powders had similar conductance behaviour vs. temperature. The gas response of the films was affected by both the grain size and firing temperature. #

Highly sensitive and selective stabilized zirconia-based mixed-potential-type propene sensor using NiO/Au composite sensing-electrode

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Incorporation of Vanadium Oxide in Silica Nanofiber Mats via Electrospinning and Sol‐Gel Synthesis

“…Dispersing V 2 O 5 nanoparticles onto the surface of silica nanofibers may allow outstanding specificity and selectivity in gas sensing to be gained. Currently, thin films containing V 2 O 5 are used for sensing toxic or flammable gases, but this method only utilizes the limited surface layer of the film because the gas flows over the film [9,10]. Nanofiber mats can provide a highly porous network which the gas can flow through, and thus the entire active sites on fibers are effectively utilized.…”

Nanostructured TiO2-based mixed metal oxides prepared using microemulsions for carbon monoxide detection

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