Effect of dopant polarizability on oxygen sublattice order in phase-stabilized cubic bismuth oxides
- 335 Downloads
- 25 Citations
Abstract
Bismuth oxide doped with isovalent rare earth cations retains the high temperature defective fluorite structure upon cooling down to room temperature. However, these doped materials undergo an order-disorder transition of the oxygen sublattice at about 600 °C. When annealed at temperatures less than the transition temperature the oxygen sublattice continues to order, and consequently oxygen ion conductivity undergoes a decay.
Modeling of ordered structures based on TEM diffraction patterns indicates a 〈111〉 vacancy ordering in the anion sublattice. Neutron diffraction studies show additional structural changes in the oxygen sublattice due to ordering. These studies indicate that the ionic conductivity is dependent on the distribution of oxygen ions between the regular 8c sites and the interstitial 32f sites in the fluorite structure.
Earlier neutron diffraction studies indicate that short range ordering of the anion sublattice is related to the polarizability of the cations. In this study we relate the stability of the disordered structure and the formation of long range order to the polarizability of the dopant cations, in terms of the time constant for conductivity decay and the dielectric constant.
Keywords
Bismuth Oxide Fluorite Structure Neutron Diffraction Study Anion Sublattice Rare Earth CationPreview
Unable to display preview. Download preview PDF.
References
- [1]T. Takahashi, H. Iwahara and Y. Nagai, J. Appl. Electrochem.2, 97 (1972).Google Scholar
- [2]T. Takahashi, H. Iwahara, T. Arao, J. Appl. Electrochem.5, 187 (1975).Google Scholar
- [3]V.G. Gattow and H. Schroder, Z. Anorg. Allg. Chem.318, 197 (1962).CrossRefGoogle Scholar
- [4]L.G. Sillen, Ark. Kemi. Mineral. Geol.12A, 1 (1937).Google Scholar
- [5]B.T.M. Willis, Acta Crystallogr.18, 75 (1965).CrossRefGoogle Scholar
- [6]E.D. Wachsman, N. Jiang, D.M. Mason, and D.A. Stevenson, Proc. Electrochem. Soc.89–11, 15 (1989).Google Scholar
- [7]M.J. Verkerk, A.J. Burggraaf, Solid State Ionics3/4, 463 (1981).CrossRefGoogle Scholar
- [8]E.D. Wachsman, G.R. Ball, N. Jiang, and D.A. Stevenson, Solid State Ionics52, 213 (1992).CrossRefGoogle Scholar
- [9]N. Jiang and E.D. Wachsman, J. Am. Ceram. Soc.82, 3057 (1999).Google Scholar
- [10]N. Jiang, R.M. Buchanan, F.E.G. Henn, A.F. Marshall, D.A. Stevenson, and E.D. Wachsman, Mater. Res. Bull.29, 247 (1994).CrossRefGoogle Scholar
- [11]N. Jiang, R.M. Buchanan, D.A. Stevenson, W.D. Nix, Ji-Zhou Li and Ji-Lian Yang, Materials Letters22, 215 (1995).CrossRefGoogle Scholar
- [12]E.D. Wachsman, S. Boyapati, M.J. Kaufman, and N. Jiang, J. Amer. Cer. Soc.83, 1964 (2000).Google Scholar
- [13]E.D. Wachsman, S. Boyapati, M.J. Kaufman, and N. Jiang, “Solid State Ionic Devices”, Proc. Electrochem. Soc.99-13, 42–51 (1999).Google Scholar
- [14]S. Boyapati, E.D. Wachsman, and B.C. Chakoumakos, Solid State Ionics138, 293 (2001).CrossRefGoogle Scholar
- [15]P.D. Battle, C.R.A. Catlow, J.W. Heap, and L.M. Moroney, J. Solid State Chem.63, 8 (1986).CrossRefGoogle Scholar
- [16]P.D. Battle, C.R.A. Catlow, J.W. Heap, and L.M. Moroney, J. Solid State Chem.67, 42 (1987).CrossRefGoogle Scholar
- [17]K. Shirao, T. Iiada, K. Kazuko, and Y. Iwadate, J. Alloys and Compounds281, 163 (1998).CrossRefGoogle Scholar
- [18]K.Z. Fung, J. Chen, and A.V. Virkar, J. Am. Ceram. Soc.76, 2403 (1993).CrossRefGoogle Scholar