Abstract

Synthesis and Characterization of Nanocrystalline Zinc Oxide Thin Films for Ethanol Vapor Sensor

Bhasha S*, Malik P, Santosh S and Purnima J

ZnO nanoparticles as gas sensors have a property of changing the electrical conductivity of the sensing element on exposure to gas atmospheres. The number, density and size distribution of particles plays a key role in gas sensing applications. The gas sensing mechanism mainly depends upon the morphology, ion occupancy and the operating temperature, which helps in adsorbing the OH- groups on the surface of oxide materials. The ethanol vapor sensing measurements have been carried out on the ZnO pellet with silver pasted electrodes on both the ends. The change in electrical resistance was used as the measure of ethanol vapor response at different temperatures in the range of 25°C to 45°C at an interval of 5°C under an ethanol concentration of 25.02, 50.05, 75.08, 100.11 and 150.17 ppm. These results showed that the indium zinc oxide film based ethanol sensor has high response quick recovery time and selectivity to the ethanol vapor.