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The Kinetics of Ordering in Gadolinium Zirconate: an Unusual Oxygen Ion Conductor

Published online by Cambridge University Press:  21 February 2011

Sossina M. Haile  and
Scott Meilicke
Sossina M. Haile
Affiliation:
University of Washington, Dept. of Materials Science and Engineering, Seattle, WA, 98195–2120
Scott Meilicke
Affiliation:
University of Washington, Dept. of Materials Science and Engineering, Seattle, WA, 98195–2120
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Abstract

Gadolinium zirconate, Gd2Zr2O7, undergoes an order-disorder transition at ∼1550°C, transforming from a defect fluorite structure (Fm3m) to a pyrochlore structure (Fd3m). Both cations and anions are ordered in the low-temperature, pyrochlore structure. In order to understand the interplay between anion and cation order parameters and ordering rates, the transformation kinetics of Gd2Zr2O7 have been examined via X-ray diffraction. Gadolinium zirconate is of particular interest because the oxygen ion conductivity of the ordered phase is significantly greatly than that of the disordered phase, in contrast to virtually every other known solid electrolyte. This difference in conductivity has provided a second technique for characterizing the transformation kinetics: in situ A.C. impedance spectroscopy. Results of the X-ray diffraction showed the growth of superstructure peak intensity to follow an apparent (time)½ dependence, rather than that expected from a nucleation and growth model. The impedance spectroscopy measurements, on the other hand, showed the conductivity to increase linearly with time. These results suggest the transition is second order in nature.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 398: Symposium C – Thermodynamics and Kinetics of Phase Transformations , 1995 , 599
Copyright
Copyright © Materials Research Society 1998

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References

REFERENCES

1 Rath, B.B. in Solid → Solid Phase Transformations. Ed. by Aaronson, H.I., Laughlin, D.E., Sekerka, R.F. and Wayman, C.M. (The Metallurgical Society of AIME, Warrendale, PA, 1982) pp. 1097–1103.Google Scholar
2 Bronsveld, P.M., Van Der Vegt, W.H.M., Van Royen, E.W. and De Hosson, J.Th.M. in Solid → Solid Phase Transformations. Ed. by Aaronson, H.I., Laughlin, D.E., Sekerka, R.F. and Wayman, C.M. (The Metallurgical Society of AIME, Warrendale, PA, 1982) pp. 243–247.Google Scholar
3 Van Dijk, M.P., De Vries, K.J. and Burggraaf, A.J., Phys. Stat. Sol. (a), 58, 115 (1980).Google Scholar
4 Moriga, T., Yoshiasa, A., Kanamaru, F., Kuto, K., Yoshimura, M. and Sômiya, S., Solid State Ionics, 31, 319, (1989).Google Scholar
5 Burggraaf, A.J., Van Dijk, T. and Verkerk, M.J., Solid State Ionics, 5, 519 (1981).Google Scholar
6 Van Dijk, M.P., Burggraaf, A.J., Cormack, A.N. and Catlow, C.R.A., Solid State Ionics, 17, 159 (1985).Google Scholar
7 Warren, B.E., X-Ray Diffraction (Dover Publications, Inc., New York, 1990) pp. 208.Google Scholar
8 Moon, P., Ph.D. Thesis, Massachusetts Institute of Technology, Cambridge, MA, 1988.Google Scholar
9 Haas, C., Phys. Rev., 140, A863 (1965).Google Scholar
10 Kingsley, J.J. and Pederson, L.R., Materials Letters, 18, 89 (1993).Google Scholar
11 Meilicke, S. and Haile, S.M., Mat. Res. Soc. Symp. Proc, April 1995, in pressGoogle Scholar
12 Soffa, W.A. and Laughlin, D.E., in Solid → Solid Phase Transformations. Ed. by Aaronson, H.I., Laughlin, D.E., Sekerka, R.F. and Wayman, C.M. (The Metallurgical Society of AIME, Warrendale, PA, 1982) pp. 159–184.Google Scholar
13 Bonanos, N., Steele, B.C.H., Butler, E.P., Johnson, W.B., Worrel, W.L., MacDonald, D.D. and McKubre, M.C.H. in Impedance Spectroscopy. Ed. by MacDonald, J.R. (John Wiley & Sons, New York, 1987) pp. 190–238.Google Scholar
14 Stauffer, D. and Aharony, A., Introduction to Percolation Theory. 2nd Ed. (Taylor & Francis, Washington, D.C., 1992).Google Scholar