Structural characterization of ZrO2 nanoparticles obtained by aerosol pyrolysis

Abstract

Fine zirconium oxide powders have been obtained by pyrolysis of an aerosol produced by ultrahigh frequency from a zirconium oxalate solution. The as-received material, obtained at 400 °C, is amorphous and constituted of hollow spherical particles. This material was annealed under different conditions producing nanometric particles of ZrO ₂ . A study of the equilibrium between the monoclinic and the cubic/tetragonal phase as a function of the thermal treatment has been performed. Crystallographic characterization of the fine zirconia particles obtained has been accomplished using electron diffraction and high-resolution electron microscopy, revealing that even individual nanometric ZrO ₂ particles could contain multiple twin variants.