Fabrication and characterization of metal doped ZnO nanostructures

In this thesis work, undoped and thallium (Tl)-doped (in the range of 1-5 mol) zinc oxide (ZnO) nanostructures were coated on microscope slides as a thin film. For thisy purpose sol-gel spin coating and hydrothermal methods were used. The obtained structures were investigated via the X-ray diffraction (XRD) method as crystallographic. All the produced structures were indexed in hexagonal (wurtzite) unit cell type. It was determined that the unit cell parameters of the ZnO nanorod structures increase with increasing the dopant amount of the Tl. The morphological properties of the produced nanorod structures was investigated by field emission scanning electron microscopy (FE-SEM). It was determined from the FE-SEM images that undoped and Tl-doped ZnO thin films have nanorod geometry. The electrical conductivity of the undoped and Tl doped ZnO thin films was measured by four-point probe dc method between room temperature and 300°C. In general, an increase in electrical conductivity was observed with Tl doping. The optical transmittance of the produced undoped and Tl doped ZnO thin films was measured by ultraviolet/visible range (UV/VIS) spectrophotometry.