WO3 nanofibers for gas sensing applications

WO3 nanofibers (NFs), with diameter of about 150–200nm, were grown using the electrospinning technique starting from WCl6 as tungsten source. The NFs were deposited onto a patterned substrate, for gas sensing measurements, and on a silicon substrate, for chemical and structural characterizations. The chemical composition of the NFs was determined by the x-ray photoemission spectroscopy, while high spatial resolution soft x-ray photoemission spectroscopy showed a chemical image of the NF. The gas sensing properties of these NFs were checked towards NO2 and CO, showing a good response for NO2 while no effect was observed for CO.

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