Optical and Structural Properties of ZnO:Au Nanocomposite Thin films

Abstract

Zinc Oxide (ZnO) nanoparticles were mixed carefully with gold (Au) nanoparticles. These chemical-compounds were used to make nanocomposite thin films by using the technique of spray pyrolysis. This work studies the XRD spectra of nanocomposite thin film of ZnO:Au, there two peaks with the orientation of (100) and (002) for the ZnO nanoparticles were found at 2θ = 31.5582 and 34.1617, which are specified by the reference of ZnO powder diffraction of card number (96-901-1663), and one peak with (111) orientation of gold nanoparticles at 2θ = 38.5799 by the reference of Au powder diffraction of card number (96-901-2431) was found. The AFM images of ZnO, Au and ZnO:Au nanocomposite thin films showed that all the specimens have a grainy nature. The results of optical properties were clearly demonstrated that when the wavelength increases the transmission increases, while the absorption coefficient, attenuation coefficient and energy gap decreases. Finally the dielectric constant measurements proved that real part dielectric constant and imaginary part dielectric constant of all trials decreases rapidly when the frequency is increasing.