Detection of acetone in air using silver ion exchanged ZSM-5 and zinc oxide sensing films

Zinc oxide (ZnO) based gas sensors with sliver ion exchanged ZSM-5 (Ag +ZSM5) zeolite overlayer were created and tested for detection of acetone vapor in air. The ZnO and Ag+ZSM-5 films were deposited on 400microm by 400microm platinum interdigitated electrodes on a silicon dioxide film on a silicon substrate. The microfabrication process of the interdigitated electrodes used for the sensors is presented. The synthesis and materials characterization of ZnO and Ag+ZSM-5 is discussed. Two types of sensors were developed, one with only a ZnO film and the other a ZnO film with Ag+ZSM-5 film on top.;The acetone sensitivity was examined by exposing both sensors to dry air containing varying parts per million acetone at 350°C then measuring the resulting change in resistance across the electrodes. Both sensors showed sensitivity to acetone in air, however, the sensitivity in the ZnO and Ag+ZSM-5 films were greater than that of just the ZnO film. The utilization of the ZnO and Ag+ZSM-5 films as sensor has potential for detection of acetone in other gaseous mixtures, to include human breath.