Enhanced Optical Properties of ZnO and CeO2-coated ZnO Nanostructures Achieved Via Spherical Nanoshells Growth On A Polystyrene Template.

In this paper, ZnO, CeO2 and CeO2-coated ZnO nanostructures were synthesised by simple and efficient low temperature wet chemical methods on Si (100) and quartz substrates. The ZnO films were prepared by a drop coating deposition method. This was then combined with a thin layer of the redox active material CeO2 to form CeO2-coated ZnO films. Spherical ZnO nanoshell structures and CeO2-coated ZnO nanoshells have been prepared using polystyrene (PS) sphere monolayer templates. The structural properties and morphologies of the nanostructures were analysed by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The nanostructure compositions are studied in more detail using secondary ion mass spectroscopy (SIMS). The optical properties of the nanostructures were measured using ultraviolet-visible (UV-Vis) absorption spectroscopy in order to ascertain the effects of the nanoshell structures and the whispering gallery modes associated with these structures on the optical properties of the deposits. Our data show UV and visible light absorption was very significantly enhanced due to this nanostructuring.