Sensitivity enhancemenet in SnO2 based gas sensors by surface decoration with platinum nanoparticles

摘要

Gas sensitivity and electronic properties of pure SnO thin films as well as those surface decorated with platinum nanoparticles were examined in different atmospheres. The SnO films were deposited onto SiO substrates by an ultrasonic spray pyrolysis (USP) technique. Then, in a separate process, Pt nanoparticles were electrochemically deposited on their surfaces. Metallic contacts were provided by silver paste printing. The sensors were examined in clean air and 500 ppm ethanol (CHOH) contaminated atmospheres at different operation temperatures in the 275 to 350 °C range. The Pt/SnO sensors proved to be 4 times more sensitive. Moreover, the maximum sensitivity of the Pt-decorated device occurred at a lower operating temperature. These observations are attributed to the catalytic activity of the Pt nanoparticles.