ABSTRACT
Mechanochemical synthesis of zirconia nanocrystalline powder was performed from
zirconium oxychloride and lithium carbonate without and with an addition of a soluble salt
(lithium chloride). The purposes of this work are to synthesize zirconia powder via a
mechanochemical process and to study the effect of soluble salt on agglomerate size and
crystallinity of nanocrystalline powder. Zirconia powder was prepared by zirconium
oxychloride and lithium carbonate without and with an addition of a soluble salt by using
planetary ball mill and heat treatment. Chemical reaction between reactant mixtures
occurs during post-milling heat treatment at 400o
C to form composite powder. The
products of this reaction consist of nanocrystalline powder embedded within lithium
chloride as soluble salt. The nanocrystalline powder is then recovered by removing
the salt through a washing procedure. The powders were characterized using X-ray
diffraction (XRD), scanning electron microscopy (SEM), and particle size analysis.
The results indicated that the structure of zirconia with addition of the lithium chloride is
transformed from monoclinic form to tetragonal form and its crystallinity depends on the
concentration of lithium chloride. Furthermore, agglomerate size of nanocrystalline
powder also depends on the concentration of lithium chloride and washing procedure.
Primary particle size of powder is approximately 30 nm.
Keywords: Zirconia, Soluble salt, Mechanochemical synthesis, X-ray diffraction