Gas Sensing Performance of Pure and Cr2O3 Modified WO3 Thick Films
نویسندگان
چکیده
The thick films of Tungsten Oxide (WO3) were prepared by screen-printing technique. Gas-sensing performance of these films was tested for various gases. The pure films showed response to Hydrogen Sulphide, Ethanol, Oxygen, and Cigar smoke. The pure WO3 thick films were surface modified by dipping them into an aqueous solution of CrO3 for different intervals of time. Surface modification improved the selectivity and response to H2S gas and suppressed the responses to other gases. The surface modification, using dipping process, altered the adsorbate-adsorbent interactions, which gave the unusual sensitivity and selectivity effect. Sensitivity, selectivity, thermal stability, response and recovery time of the sensor were measured and presented.
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