Studies on Zinc Oxide Thin Film and Nanoparticles Synthesized by Chemical Bath Deposition

Zinc Oxide (ZnO) nanoparticles (NPS) and thin film are synthesized by chemical bath deposition technique. Synthesized nanoparticles and thin film are characterized by X-ray diffraction (XRD), Transmission electron microscope (TEM), UV–Visible spectroscopy, Photoluminescence spectroscopy (PL) and Raman Spectroscopy. XRD analysis shows that ZnO NPS and thin film are formed in hexagonal wurtzite structure. A particle size of NPS varies from 40–60 nm, which is confirmed with TEM. UV–Vis absorbance spectrum shows absorption peak at ~ 369.2 nm (3.36 eV) for thin film and at ~ 378.8 nm (3.27 eV) for nanoparticles. Determined band gap from Uv–Vis absorption are 3.11 and 2.81 eV for ZnO thin film and NPS respectively. PL spectra of thin film and NPS show multiple peaks for violet, blue and green emissions which may be attributed to various defect levels present in material. Raman spectrum of ZnO nanoparticles shows presence of different Raman – active modes. Presence of sharp peak for non-polar optical phonons E2 (high) mode confirms good quality hexagonal wurtzite crystal phase of ZnO nanoparticles.