Low Temperature Operated NO2 Gas Sensor Based on SnO2-ZnO Nanocomposite Thin Film

Nanocrystalline composite thin films of Zinc oxide and Tin oxide (ZSO) have been synthesized using chemical route for the efficient trace level (20 ppm) detection of NO2 gas at lower operating temperature. The prepared ZSO sensor structure showed a high sensing response of about 1.578 x 10(3) towards 20 ppm of NO2 gas at a lower operating temperature of 70 degrees C with an average response and recovery time of 3.91 min. and 6.91 min. respectively. The structural, optical and surface morphological properties of the ZSO composite thin film have been studied by X-ray diffraction (XRD), UV-Visible spectroscopy, Atomic Force microscopy (AFM) images and have also been correlated with the observed enhancement in gas sensing properties of prepared sensor structure.