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Analytical electron microscopy of planar faults in SrO-doped CaTiO3

Published online by Cambridge University Press:  31 January 2011

M. Čeh ,
H. Gu ,
H. Müllejans  and
A. Rečnik
M. Čeh
Affiliation:
“J. Stefan” Institute, Jamova 39, 1000 Ljubljana, Slovenia
H. Gu
Affiliation:
Max-Planck-Institut für Metallforschung, Seestraße 92, 70174 Stuttgart, Germany
H. Müllejans
Affiliation:
Max-Planck-Institut für Metallforschung, Seestraße 92, 70174 Stuttgart, Germany
A. Rečnik
Affiliation:
“J. Stefan” Institute, Jamova 39, 1000 Ljubljana, Slovenia, and Max-Planck-Institut für Metallforschung, Seestraße 92, 70174 Stuttgart, Germany
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Abstract

Oxide-rich planar faults within a perovskite matrix are the prevailing type of extended defects in polycrystalline SrO-doped CaTiO3. These defects form, depending on the temperature of sintering, random networks, or ordered structures. The chemistry of the polytypoid, the isolated planar faults, and the perovskite phase have been studied by spatially resolved electron energy-loss and energy-dispersive x-ray spectroscopies using a dedicated scanning transmission electron microscope. We have found that Sr ions from SrO additions preferably substitute Ca in the CaTiO3 lattice, thus forming a solid solution (Ca1–xSrx)TiO3. The surplus of Ca ions forms single and ordered CaO-rich planar faults in the host (Ca1–xSrx)TiO3 phase. Whereas the excess Ca segregates in a form of single planar faults at lower temperatures, it forms a stable polytypoidic phase at higher temperatures. For materials having up to 25 mol% of SrO additions, this phase has (Ca1–xSrx)4Ti3O10 composition, comprising a sequence of CaO faults followed by three (Ca1–xSrx)TiO3 perovskite layers. Analytical electron microscopy revealed that the composition of the single planar faults, formed at lower temperatures, is identical to that of polytypoids, which are stable at higher sintering temperatures.

Type
Articles
Information
Journal of Materials Research , Volume 12 , Issue 9 , September 1997 , pp. 2438 - 2446
Copyright
Copyright © Materials Research Society 1997

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References

REFERENCES

1.Herbert, J. M., Ceramic Dielectrics and Capacitors; Electrocomponent Science Monographs, Vol. 6 (Gordon and Breach Science Publishers, New York, 1985), pp. 152, 226.Google Scholar
2.Hench, L. L. and West, J. K., Principles of Electronic Ceramics (John Wiley & Sons Inc., New York, 1990), pp. 185, 237.Google Scholar
3.Wakino, W., Ferroelectrics 91, 69 (1989).CrossRefGoogle Scholar
4.Ringwood, A. E., Kesson, S. E., Ware, N. G., Hibbertson, W., and Major, A., Nature (London) 278, 219 (1979).Google Scholar
5.Ringwood, A. E., Reeve, K. D., and Tewhey, J. D., in Scientific Basis for Nuclear Waste Management: Vol. 3, edited by J. G., Moore (Plenum Press, New York, 1981), p. 147.CrossRefGoogle Scholar
6.Čeh, M. and Kolar, D., in Emerging Materials by Advance Processing, edited by Kaysser, W. A. and Weber-Bock, J. (Proceedings of IXth German-Yugoslav Meeting on Materials Science and Development, Hirsau/Stuttgart, 1989), p. 359.Google Scholar
7.Koopmans, H. J. A., van de Velde, G. M. H., and Gellings, P. J., Acta Crystallogr. C39, 1323 (1983).Google Scholar
8.Sasaki, S., Prewitt, C. T., and Bass, Y. D., Acta Crystallogr. C43, 1668 (1987).Google Scholar
9.Naylor, B. F. and Cook, O. C., J. Am. Chem. Soc. 68, 1003 (1946).Google Scholar
10.Ruddlesden, S. N. and Popper, P., Acta Crystallogr. 11, 54 (1958).Google Scholar
11.Tilley, R. J. D., J. Solid State Chem. 21, 293 (1997).Google Scholar
12.Udayakumar, K. R. and Cormack, A. N., J. Am. Ceram. Soc. 71, C469 (1988).Google Scholar
13.DeVries, R. C., Roy, R., and Osborn, E. F., J. Phys. Chem. 58, 1069 (1954).Google Scholar
14.Roth, R. S., J. Res. Natl. Bur. Standards 52, 37 (1954).Google Scholar
15.Elcombe, M. M., Kisi, E. H., Hawkins, K. D., White, T. J., Goodman, P., and Matheson, S., Acta Crystallogr. B47, 305 (1991).CrossRefGoogle Scholar
16.Jongean, A. and Wilkins, A. L., J. Less-Comm. Met. 20, 152 (1989).Google Scholar
17.Čeh, M. and Kolar, D., J. Mater. Sci. 29, 6295 (1994).Google Scholar
18.Čeh, M., Kraševec, V., and Kolar, D., J. Solid State Chem. 103, 263 (1993).CrossRefGoogle Scholar
19.Čeh, M. and Rečnik, A., Microscopia Elettronica 14 (2) Suppl., 281 (1993).Google Scholar
20.Rečnik, A., Čeh, M., and Ernst, F., in Electron Microscopy 1994: Interdisciplinary Developments and Tools, edited by Jouffrey, B. and Colliex, C. (Proceedings of 13th International Congress on Electron Microscopy, Paris, 1994), p. 405.Google Scholar
21.Kwestroo, W. and Paping, H. A. M., J. Am. Ceram. Soc. 42, 292 (1959).Google Scholar
22.Kramer, H. A., Philos. Mag. 46, 836 (1923).Google Scholar
23.Cliff, G. and Lorimer, G. W., J. Microsc. 103, 203 (1975).CrossRefGoogle Scholar
24.Ikeda, J. A. S., Chiang, Y. M., Garratt-Reed, A. J., and Vander Sande, J. B., J. Am. Ceram. Soc. 76, 2447 (1993).CrossRefGoogle Scholar
25.Müllejans, H. and Bruley, J., Ultramicroscopy 53, 351 (1994).Google Scholar
26.Gu, H., Čeh, M., Stemmer, S., Müllejans, H., and Rühle, M., Ultramicroscopy 59, 215 (1995).CrossRefGoogle Scholar
27.Udayakumar, K. R. and Cormack, A. N., J. Phys. Chem. Solids 50, 55 (1989).Google Scholar