Investigation of sensitivity and selectivity of ZnO thin film to volatile organic compounds

This research addresses a detailed study on thesensitivity and selectivity of ZnO thin film to volatileorganic compound (VOC) vapors that can be used for thedevelopment of VOC sensors. The ZnO thin film of100 nm thickness was prepared by post-annealing ofe-beam evaporated Zn thin film. The sample was structurally,morphologically, and chemically characterized byX-ray diffraction and field emission scanning electronmicroscopy analyses. The sensitivity, selectivity, anddetection limit of the sample were tested with respect to awide range of common VOC vapors, including acetone,formaldehyde, acetic acid, formic acid, acetylene, toluene,benzene, ethanol, methanol, and isopropanol in the temperaturerange of 200–400 ̊ C. The results show that thebest sensitivity and detection limit of the sample are relatedto acetone vapor in the studied temperature range. The ZnOthin film-based acetone sensor also shows a good reproducibilityand stability at the operating temperature of280 ̊ C.