Shivanand G. Sonkamblea and Anil B. Gambhire
Nanosize tin dioxide based powders containing silver oxide and palladium have been prepared by coprecipitation reaction. The material obtained is nanocrystalline, having particle size in the range from 5.21 to 7.42 nm and decreases with increasing amount of doping silver. High selective and sensitive thick-film gas sensors were fabricated and their sensing characteristics for H2S and other toxic gases were investigated at the operating temperature of 70°C. Pd-added, silver doped-SnO2 thick-film sensor exhibited high sensitivity to H2S gas of 1-10 ppm and had good selectivity to H2S gas than that of the other gases (1000 ppm). This material (Pd + Ag2O/SnO2, Pd = 1.5 wt. %, Ag = 3 wt.% sintered at 600°C with an optimal temperature of 70°C) may prove to have tremendous potential for H2S gas sensing applications.
