Synthesis, Optical, and Morphological Studies of ZnO Powders and Thin Films Fabricated by Wet Chemical Methods

Zinc oxide nanoparticles were prepared from Zn₅(CO₃)₂(OH)₆ precursor, capped with poly(vinylpyrrolidone) (PVP), and annealed at 600 °C. The obtained powders were characterized by a powder X-ray diffraction (PXD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV-visible spectroscopy (UV-vis), Raman spectroscopy, infrared spectroscopy (IR), thermal analysis (TGA/DTA), and third-order nonlinear (NL) optical measurement. Morphological evaluation by TEM and SEM measurements indicated that the precursor micro-particles are ball-shaped structures composed of plates with a thickness of approximately 10 nm. ZnO thin films, as well as ZnO/polymer multilayer layouts, were obtained by wet chemical methods (spin- and dip-coating). Surface topography and morphology of the obtained films were studied by SEM and AFM microscopy. Films with uniformly distributed ZnO plates, due to the erosion of primary micro-particles were formed. The fabricated specimens were also analyzed using a spectroscopic ellipsometry in order to calculate dielectric function and film thickness.