STRUCTURAL CHARACTERIZATION OF ZRO2 NANOPARTICLES OBTAINED BY AEROSOLPYROLYSIS

Fine zirconium oxide powders have been obtained by pyrolysis of an aer osol produced by ultrahigh frequency from a zirconium oxalate solution . The as-received material, obtained at 400 degrees C, is amorphous an constituted of hollow spherical particles. This material was annealed under different conditions producing nanometric particles of ZrO2. A study of the equilibrium between the monoclinic and the cubic/tetragon al phase as a function of the thermal treatment has been performed. Cr ystallographic characterization of the fine zirconia particles obtaine d has been accomplished using electron diffraction and high-resolution electron microscopy, revealing that even individual nanometric ZrO2 p articles could contain multiple twin variants.