Preparation And Physical And Chemical Properties Of Zno Based Nano-film Research

As a member of the II-VI compound semiconductors zinc oxide (ZnO) has been under an extensive research in recent years for its unique physicochemical properties. It has been widely used in many different applications, such as optoelectronic devices, chemisorption gas sensors, as well as photo-degradation materials, etc. Doping with different elements can improve the property of materials. So it is significant to do the research on the preparation and physicochemical properties of ZnO-based thin films.In this paper, ZnO-based nano powders and thin films were prepared by sol-gel dip coating method with zinc acetate dihydrate, ethanol and 2-ethanolamine as the starting material, solvent and stabilizer, respectively. The sol, powder and its thin films were characterized by UV-Vis, TG, XRD, IR, AFM and EDS methods. The gas-sensing properties of the ZnO-based multilayers for alcohols with different chain lengths were studied at room temperature. The results show that the doping of Ti element can decrease the resistance of ZnO thin film. Cu doped ZnO thin film can detect 100 ppb propyl alcohol vapor, while Mn doped ZnO thin film exhibits high sensitivity to NH3 and H2O vapor.Furthermore, the photoluminescence properties of ZnO and Tb doped ZnO thin films, heat-treated in different atmospheres, were carried out. When the pure ZnO film was annealed in N2 atmosphere, its blue emission was obviously increased. The main photoluminescence emission of thin films shifted from blue to ultraviolet after it was doped with Tb. When the pure ZnO film sintered in H2 atmoshpere, however, the ultraviolet emission can be greatly improved.The photo degradation properties of ZnO-based materials have been further investigated. The ZnO powders exhibited good photo-degradation effect to salicylic acid and the degradation properties of Ti doped powder can be efficiently improved.