Application of nanosize polycrystalline SnO$_{2}$-WO$_{3}$ solid material as CO$_{2}$ gas sensor

Abstract

Among binary metal oxide sensors, tin oxide based sensors have received more attention, due to its high reactivity to many gases. The nanosize SnO$_{2}$-WO$_{3}$ polycrystalline solid material of different mol% was prepared to form thin films by screen printing method. The sensitivity of the films is measured for different concentration of CO$_{2}$ gas at room temperature (303K). The variation of sensitivity with CO$_{2}$ gas concentration is found to be linear. The sensor 40SnO$_{2}$-60WO$_{3}$ shows maximum sensitivity in presence of CO$_{2}$ gas. The static and dynamic response of the sensors was studied. The reproducibility and stability for all sensors was good. The average crystallite size was calculated from XRD spectra and found to be of the order of 17.11 to 17.17 nm except pure WO$_{3}$ film has 22.91 nm.