Application of a modified ultrasonic aerosol device to the synthesis of SnO2 and Pt/SnO2 for gas sensors

SnO2 and Pt/SnO2 powders were synthesized with a modified ultrasonic aeroso l pyrolysis device. The advantages of this new method were tested by compar ison of pure SnO2 powders synthesized by conventional and modified aerosol methods. Then, the synthesis of SnO2 with Pt was carried out by this new me thod, The droplet evaporation and pyrolysis processes induce the formation of materials with a fine microstructure that exhibit, after annealing, a hi gh sensitivity to ethanol or CO in air. In the Pt/SnO2 powders, platinum ag gregates dispersed onto the SnO2 grains improve the sensitivity of SnO2 pow ders when the sample is annealed at 700 degrees C, Therefore, a Pt/SnO2 sam ple submitted to such thermal treatment is a good candidate for CO and C2H5 OH detection due to its sensitivity to both gases, (C) 1999 Academic Press.