Journal of Nanoparticle Research

, Volume 8, Issue 6, pp 1003–1016

Phases and phase transformations in nanocrystalline ZrO2

  • D. Vollath
  • F. D. Fischer
  • M. Hagelstein
  • D. V. Szabó
Article

DOI: 10.1007/s11051-006-9116-3

Cite this article as:
Vollath, D., Fischer, F.D., Hagelstein, M. et al. J Nanopart Res (2006) 8: 1003. doi:10.1007/s11051-006-9116-3

Abstract

Starting from results from He-pycnometry, electron diffraction, Extended X-ray Absorption Fine Structure Spectroscopy and Perturbed Angular Correlation Spectroscopy the phase transformations and structures of zirconia are described. From a comparison of these results with those obtained on other oxide nanoparticles it is concluded that the phases and structure of nanoparticles are different compared to those of coarse-grained material. The difference of the transformation temperature of bare and coated nanoparticles was used to estimate enthalpy and entropy of the tetragonal → monoclinic transformation for nanoparticulate zirconia. By comparison with results obtained from other nanocrystalline oxides, the following rules were derived: Provided the particles are sufficiently small, particles made of materials showing phase transitions crystallize in the high temperature structure. However, compared to coarse-grained materials of the same structure, the density of nanoparticles is reduced. A first estimation limits this phenomenon to particle sizes well below 10 nm. Those nanoparticles follow the generalized phase diagram postulated by Tammann.

Keywords

chemical synthesisnanoparticlesphase transformationsorder-disorder phenomenaperturbed angular correlationEXAFS

Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • D. Vollath
    • 1
  • F. D. Fischer
    • 2
  • M. Hagelstein
    • 3
  • D. V. Szabó
    • 4
  1. 1.NanoConsultingStutenseeGermany
  2. 2.Montanuniversität Leoben, Institute of␣MechanicsErich Schmid Institute of Materials Science, Austrian Academy of SciencesLeobenAustria
  3. 3.Forschungszentrum KarlsruheInstitut für SynchrotronstrahlungKarlsruheGermany
  4. 4.Forschungszentrum KarslruheInstitut für Materialforschung IIIKarslruheGermany