ETHANOL AND TRIMETHYL AMINE SENSING BYZnO-BASED NANOSTRUCTURED THIN FILMS

Abstract

Undoped and fluorine (F)-doped nanostructured zinc oxide ( ZnO ) thin films were deposited over glass substrates by spray pyrolysis technique using zinc acetate dihydrate with and without ammonium fluoride as dopant in precursor solution respectively. The deposition conditions and the concentration of the dopant were optimized to obtain nanostructured ZnO thin films. The film obtained from 0.05 M of zinc acetate aqueous solution and 20% F sprayed at the rate of 3 ml/min on preheated substrate kept at 503 K yielded spherical shape well-connected grains, which has large surface to volume ratio. The structural and morphological studies of the films were investigated by using X-ray diffraction (XRD) and scanning electron microscope (SEM) respectively. The diffraction peak positions in XRD confirmed the formation of highly crystalline ZnO film with hexagonal wurtzite phase. Further sensing behavior of the films towards various concentrations of volatile organic compounds (VOCs) such as ethanol and trimethyl amine (TMA) has been investigated at an optimized operating temperature of 373 K and reported.