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Hydrothermal Coarsening of CeO2 Particles

Published online by Cambridge University Press:  31 January 2011

S. Lakhwani
Affiliation:
Department of Ceramic Engineering, University of Missouri, Rolla, Missouri 65409
M. N. Rahaman
Affiliation:
Department of Ceramic Engineering, University of Missouri, Rolla, Missouri 65409
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Abstract

The effects of reaction temperature (150–300 °C), chemical composition of the starting cerium salt (cerium nitrate and cerium chloride), and doping with trivalent cations (Sc3+ and Y3+) on the coarsening of CeO2 particles in dilute suspensions under hydrothermal conditions were investigated. The particle size was measured by x-ray line broadening and by transmission electron microscopy. The particle coarsening kinetics followed a parabolic law, indicating that the interfacial reaction (dissolution) was the rate-controlling step. Furthermore, the particle size distribution data can be well-described by the Lifshitz–Slyozov–Wagner theory of Ostwald ripening controlled by the interfacial reaction. Doping with 6 at.% Y3+ produced a significant reduction in the coarsening rate but almost no change in the activation energy. At the same concentration, Sc3+ was more effective than Y3+ in reducing the coarsening rate. Particles synthesized from a starting solution of cerium(III) chloride coarsened at a markedly slower rate than that for particles synthesized from cerium(III) nitrate. The mechanisms controlling the coarsening of the particles are discussed.

Type
Articles
Copyright
Copyright © Materials Research Society 1999

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References

REFERENCES

1.Dawson, W.J., Am. Ceram. Soc. Bull. 67, 1673 (1988).Google Scholar
2.Zhou, Y. C. and Rahaman, M. N., J. Mater. Res. 8, 1680 (1993).CrossRefGoogle Scholar
3.Rahaman, M.N. and Zhou, Y.C., J. Europ. Ceram. Soc. 15, 939 (1995).CrossRefGoogle Scholar
4.Yang, X. and Rahaman, M.N., J. Europ. Ceram. Soc. 17, 525 (1997).CrossRefGoogle Scholar
5.Tani, E., Yoshimura, M., and Sōmiya, S., J. Mater. Sci. Lett. 1, 461 (1982).CrossRefGoogle Scholar
6.Hirano, M. and Kato, E., J. Am. Ceram. Soc. 79, 777 (1996).CrossRefGoogle Scholar
7.Greenwood, G.W., Acta Metall. 4, 243 (1956).CrossRefGoogle Scholar
8.Wagner, C., Z. Electrochem. 65, 581 (1961).Google Scholar
9.Lifshitz, I. M. and Slyozov, V. V., J. Phys. Chem. Solids 19, 35 (1961).CrossRefGoogle Scholar
10.Klug, H.P. and Alexander, L. E., X-Ray Diffraction Procedures, 2nd ed. (Wiley, New York, 1974).Google Scholar
11.Shannon, R.D. and Prewitt, C.T., Acta Crystallogr. B25, 925 (1969).CrossRefGoogle Scholar
12.Shannon, R.D., Acta Crystallogr. A32, 751 (1976).CrossRefGoogle Scholar
13.Eshelby, J. D., in Solid State Physics, edited by Seitz, F. and Turnbull, D. (Academic Press, New York, 1956), Vol. 3, p. 79.Google Scholar
14.Frenkel, J., Kinetic Theory of Liquids (Oxford University Press, New York, 1946), p. 36.Google Scholar
15.Lehovec, K., J. Chem. Phys. 21, 1123 (1953).CrossRefGoogle Scholar