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Meltspun Ba8Ga16−xGe30+x clathrates

Published online by Cambridge University Press:  05 August 2011

S. Laumann ,
M. Ikeda ,
H. Sassik ,
A. Prokofiev  and
S. Paschen
S. Laumann
Affiliation:
Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
M. Ikeda
Affiliation:
Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
H. Sassik
Affiliation:
Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
A. Prokofiev
Affiliation:
Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
S. Paschen*
Affiliation:
Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Ba8Ga16−xGe30+x is the clathrate with the highest thermoelectric figure of merit known to date. However, no p-type material could be obtained by conventional synthesis from the melt. Here we show that the time and cost-effective melt spinning technique can produce Ba8Ga16−xGe30+x in a metastable state, where x can be varied continuously from negative to positive values, resulting in both p- and n-type materials. The quenched phases were characterized by x-ray powder diffraction and transmission electron microscopy. It was surprising that they were perfectly crystalline, with large grain sizes of the order of a micrometer. Temperature dependent measurements of the electrical resistivity, Hall effect, thermopower, and thermal conductivity are presented and discussed in terms of a two-band model.

Keywords

clathratesthermoelectricrapid solidification
Type
Articles
Information
Journal of Materials Research , Volume 26 , Issue 15: Focus Issue: Advances in Thermoelectric Materials , 14 August 2011 , pp. 1861 - 1865
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1.Madsen, G., Schwarz, K., Blaha, P., and Singh, D.: Electronic structure and transport in type-I and type-VIII clathrates containing strontium, barium, and europium. Phys. Rev. B 68, 125212 (2003).CrossRefGoogle Scholar
2.Norihiko, L., Kishida, K., Tanaka, K., and Inui, H.: Crystal structure and thermoelectric properties of type-I clathrate compounds in the Ba8Ga16Ge30 system. J. Appl. Phys. 100, 073504 (2006).Google Scholar
3.Bertini, L., Billquist, K., Bryan, D., Christensen, M., Gatti, C., Holmgren, L., Iversen, B.B., Mueller, E., Muhammed, M., Noriega, G., Palmqvist, A.E.C., Platzek, D., Rowe, D.M., Saramat, A., Stiewe, C., Stucky, G.D., Svensson, G., Toprak, M., Williams, S.G.K., and Zhang, Y.: Thermoelectric performance of large single crystal clathrate Ba8Ga16Ge30. In Proceedings of the 22nd International Conference on Thermoelectrics (IEEE, Piscataway, NJ, 2003), p. 127.Google Scholar
4.Anno, H., Hokazono, M., Kawamura, M., Nagao, J., and Matsubara, K.: Thermoelectric properties of Ba8GaxGe46−x clathrate compounds. In Proceedings of the 21st International Conference on Thermoelectrics (IEEE, Piscataway, NJ, 2002), p. 77.Google Scholar
5.Prokofiev, A., Paschen, S., Sassik, H., Laumann, S., Pongratz, P.: Method for producing clathrate compounds. Utility patent AT: 10749 U1 2009-09-05, DE: 20 2008 006 946.7, patent applications U.S.: 12/231,183, JP: 135994/2008.Google Scholar
6.Paschen, S., Gspan, C., Grogger, W., Dienstleder, M., Laumann, S., Pongratz, P., Sassik, H., Wernisch, J., and Prokofiev, A.: Investigation of Yb substitution in the clathrate phase Eu8Ga16Ge30. J. Cryst. Growth 310, 1853 (2008).CrossRefGoogle Scholar
7.Li, H., Tang, X., and Zhang, Q.: Microstructure and thermoelectric properties of Yb-filled skutterudites prepared by rapid solidification. J. Electron. Mater. 38, 7 (2009).CrossRefGoogle Scholar
8.Kim, T-S. and Chun, B-S.: Microstructure and thermoelectric properties of n- and p-type Bi2Te3 alloys by rapid solidification processes. J. Alloys Compd. 437, 225 (2007).CrossRefGoogle Scholar
9.Ebling, D.G., Jacquot, A., Jägle, M., Böttner, H., Kühn, U., and Kirste, L.: Structure and thermoelectric properties of nanocomposite bismuth telluride prepared by melt spinning or by partially alloying with IV–VI compounds. Phys. Status Solidi (RRL) 1, 238 (2007).Google Scholar
10.Schäfer, H.: On the problem of polar intermetallic compounds: The stimulation of E. Zintl’s work for the modern chemistry of intermetallics. Annu. Rev. Mater. Sci. 15, 1 (1985).CrossRefGoogle Scholar