Preparation and properties of zinc oxide nanoparticles coated with zinc aluminate

Abstract

Zinc oxide nanoparticles coated with zinc aluminate have been prepared by performing Al₂O₃ precipitation on the precursor basic carbonate of zinc (BCZ) of zinc oxide. TEM shows that a homogeneous layer is formed on the surface of the zinc oxide nanoparticles, and the coated particle size is about 50–60 nm. The thickness of the layer estimated by high magnification transmission electronic micrography is about 4–5 nm. Results of X-ray photoelectron spectroscopy (XPS) show that the elements in the coating at the surface of the ZnO nanoparticles are Zn, O and Al. X-Ray diffraction and lattice fringe data show that the coating is of the ZnAl₂O₄ phase formed by the reaction of basic carbonate of zinc and basic carbonate of aluminium. The zinc aluminate coating is effective in reducing the catalytic activity of zinc oxide nanoparticles. Zinc oxide nanoparticles coated with zinc aluminate not only retain a high UV absorptivity, but also increase their reflectance of visible light.