Synthesis of Zinc Oxide Nanostructured Thin Film by Sol- Gel Method and Evaluation of Gas Sensing Properties

Ethanol (C2H6O) sensitivity of zinc oxide (ZnO) thin film has been studied in present work. Semiconductor thin films of zinc oxide (ZnO) were deposited onto alkali-free glass substrates by the sol–gel method and dip-coating technique. The ZnO sol was synthesized by dissolving zinc acetate dehydrate in ethanol, and then adding Tetra ethanol-amine. The as-coated films were preheated at 150 ºC for 10 min and annealed at 500 ºC for 1 h in air ambiance. Fundamental features of a sensor element e.g. sensitivity, response time and recovery process has been studied using X-ray diffraction, and Scanning Electron Microscopy. The sensitivity to ethanol was desirable and Response and recovery time were only 8 sec. and 4 sec., respectively.