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The Bismuth-Barium Oxides

Published online by Cambridge University Press:  16 February 2011

K. Müller ,
J.K. Meen  and
D. Elthon
K. Müller
Affiliation:
Department of Chemistry and Texas Center for Superconductivity, University of Houston, TX 77204, kmuelle2@bayou.uh.edu
J.K. Meen
Affiliation:
Department of Chemistry and Texas Center for Superconductivity, University of Houston, TX 77204, kmuelle2@bayou.uh.edu
D. Elthon
Affiliation:
Department of Chemistry and Texas Center for Superconductivity, University of Houston, TX 77204, kmuelle2@bayou.uh.edu
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Abstract

Phase relations have been determined for the Bi-Ba oxide pseudobinary up to 50 cat % Ba in 1 atm of oxygen at 640°-1000°C. The low-temperature α-Bi2O3 polymorph does not dissolve appreciable BaO. All other phases in the system have significant ranges of solution. The δ-Bi2O3 polymorph, stable from 730°C to 825°C is an end-member of a face-centered cubic solid solution (FCCss) that dissolves up to 2.7 % Ba. Ba-saturated FCCss and Bi-saturated rhombohedral (ß) solid solution (6.3 % Ba) melt at a eutectic at 753 °C. Less Bi is needed to saturate the ß phase at lower temperatures so α-Bi2O3 coexists with a ß phase containing 11.5 % Ba at 646°C.

The amount of Ba required to saturate the ß phase depends less strongly on temperature. Ba-saturated ß phase contains 19 % Ba at 700°C. These ß materials are in equilibrium with an oxide near Bi3BaO5.5 that undergoes two polymorphic transformations: low-temperature cubic (<700°C); orthorhombic (700-730°C); high-temperature cubic (Cht). There is a eutectic between the ß and Cht, at 775±6°C. At T<700°C, 26.5 % Ba saturates the latter but it can take in up to 29.5 % Ba (at 812°C). At T<815°C the coexisting phase is BiBaO3. A tetragonal (T) phase forms by reaction of Ch, and BiBaO3 and has ~35% BaO at 815°C. The composition span of T widens as temperature increases. Cht, melts incongruently at 820°C to a liquid and T with 29.8 % Ba. Above that temperature the Bi-saturated and Ba-saturated T phases both become more Ba-rich as temperature is elevated. T melts incongruently to liquid and BiBaO3.

The δ-Bi2O3 and ß, both anion conductors, have structures based on that of fluorite. The other oxides have perovskite-like structures. Half of the Bi in BiBaO3 is pentavalent and half is trivalent. The other oxides appear to have all their Bi in the 3+ state.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 547: Symposium DD – Solid-State Chemistry of Inorganic Materials II , 1998 , 261
Copyright
Copyright © Materials Research Society 1999

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References

1. Gattow, G., Schröder, H., Z. Anorg. Allg. Chem. 318, 176 (1962).Google Scholar
2. Levin, E.M., Roth, R.S., J. Res.Nat. Bur. Stand. 68A, 189 (1964).Google Scholar
3. Harwig, H.A., Z. anorg. allg. Chem. 444, 151 (1978).Google Scholar
4. Aurivillius, B., Arkiv För Kemi 16A, 1 (1943).Google Scholar
5. Takahashi, T., Esaka, T., and Iwahara, H., J. Solid State Chem. 16, 317 (1976).Google Scholar
6. Conflant, P., Boivin, J.C., Nowogrocki, G. and Thomas, D., Solid State Ionics 9&10, 925 (1983).Google Scholar
7. Gökçen, O.A., Kim, S., Meen, J.K., Elthon, D., and Jacobson, A.J., accepted by Solid State Ionics V, edited by Nazri, G-A., Julien, C., and Rougier, A. (Mater. Res. Soc. Proc. 548, Boston, MA, 1998).Google Scholar
8. Lee, T.H., PhD Thesis, University of Houston (1996).Google Scholar
9. Abbattista, F., Hervieu, M., Vallino, M., Michel, C., and Raveau, B., J. Solid State Chem. 104, 338 (1993).Google Scholar
10. Michel, C., Pelloquin, D., Hervieu, M., and Raveau, B., J. Solid State Chem. 109, 122 (1994).Google Scholar
11. Moudallal, H.S., PhD thesis, University of Houston (1997)Google Scholar
12. Klinkova, L.A., Barkovskii, N.V., Filatova, M.V., and Shevchenko, S.A., Superconductivity 5, 1630 (1992).Google Scholar
13. Puettner, A., PhD thesis, Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany (1993).Google Scholar
14. Thornton, G. and Jacobson, A.J., Acta Cryst. B34, 351 (1977).Google Scholar
15. Cox, D.E. and Sleight, A.W., Acta Cryst. B35, 1 (1979).Google Scholar
16. Itoh, M., Sawada, T., Liang, R, Kawaji, H., and Nakamura, T., Solid State Ionics 49, 57 (1991).Google Scholar
17. Reis, K., Jacobson, A.J., J. Solid State Chem. 107, 428 (1993).Google Scholar
18. Whitler, J.D. and Roth, R.S., in Phase Diagrams for High TC Superconductors, edited by Whitler, J.D. and Roth, R.S. (The American Ceramic Society, Westerville, OH, 1991), p. 126.Google Scholar
19. Shevchuk, A.V., Skorikov, V.M., Kargin, Yu.F., and Konstantinov, V.V., Russ. J. Inorg. Chem. (Engl. Transl.) 30 [6], 866 (1985).Google Scholar