Effect of Morphology on the Photocatalytic Behavior of ZnO Nanostructures: Low Temperature Sonochemical Synthesis of Ni Doped ZnO Nanoparticles

Abstract

In the present study, ZnO nanostructure has been synthesized by different methods, namely coprecipitation, hydrothermal and sonochemical methods. After comparison of the morphology and photocatalytic activity of ZnO samples prepared via different methods, the best method (sonochemical method) was used for synthesis of Ni-ZnO nanoparticles with different concentrations of nickel. Furthermore, structural and optical properties were investigated by Fourier Transform Infrared spectroscopy, UV–Vis spectroscopy, Field Emission Scanning Electron Microscopy, X-Ray Diffraction, and Photoluminescence spectroscopy methods. Morphology of nanoparticles prepared via sonochemical method were obtained small granular shape. In addition, the direct band gap has been calculated by Tauc's approach. Compared with pure ZnO, the band gap of the Ni-ZnO NPs is smaller and depends on the content of dopants. Moreover, photocatalytic activity of all samples has been investigated under UV irradiation in an aqueous medium. In addition, photocatalytic activity is improved in the presence of an appropriate amount of nickel dopant.