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Thermoelectric and Thermomagnetic Transport in PbTe with Nanoscale Structures

Published online by Cambridge University Press:  01 February 2011

Joseph P. Heremans
Joseph P. Heremans*
Affiliation:
[email protected], Ohio State University, Mechanical Engineering and Physics, 650 Ackerman Road, Columbus, Ohio, 43202, United States, 614 247 8869, 614 292 3163
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Abstract

Quantum-dot superlattices (QDSLs) have demonstrated thermoelectric figure of merit (ZT) values double those of classical bulk materials, providing the proof that nanoscale materials can address this age-old limitation on thermoelectric technology. Since QDSL materials can only be obtained in thin-film form, the development of bulk materials with nanoscale inclusions would be useful for many large-scale applications. Nanometer-scale inclusions in lead chalcogenides are known to improve the thermoelectric figure of merit through a combination of two factors: a strong decrease in lattice thermal conductivity, and an increase in the Seebeck coefficient over that of bulk PbTe for a given carrier concentration. This paper focuses on experimental results obtained on two types of PbTe nanocomposites, namely samples prepared by sintering powders with nanometer-sized grains, and samples prepared with nanoprecipitates of metallic Pb. The results are analyzed using the “method of four coefficients.” At each measurement temperature there are four unknowns. These are the carrier concentration, the mobility, the carrier effective mass, and the energy dependence of the relaxation time Tau, which is modeled by a power law: Tau proportional to energy to power Lamda. Therefore, at each temperature, four measurements are taken: the electrical conductivity, and the Hall, Seebeck and transverse Nernst-Ettingshausen coefficients. This analysis concludes that the effect of the nanoscale inclusions on the power factor is due to an increase in the scattering parameter λ, and that the nanoscale inclusions affect the electron scattering in such a way as to increase the Seebeck coefficient.

Keywords

nanostructurethermoelectricityelectrical properties
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 886: Symposium F – Materials and Technologies fore Direct Thermal-to-Electric Energy Conversion , 2005 , 0886-F04-10
Copyright
Copyright © Materials Research Society 2006

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References

REFERENCES

1 Harman, T.C., Taylor, P. J., Walsh, M. P., and LaForge, B. E., Science 297, 2229 (2002)Google Scholar
2 Harman, T. C., Walsh, M. P., Laforge, B. E. and Turner, G. W., Electron, J.. Mat. 34 L19 (2005)Google Scholar
3 Hicks, L.D. and Dresselhaus, M.S., Phys. Rev. B 47, 12727 (1993).Google Scholar
4 Heremans, J.P., Thrush, C. M., Morelli, D. T., and Wu, M-C., Phys. Rev. Lett. 88, 216801 (2002).Google Scholar
5 Heremans, J., Thrush, C. M., Lin, Y-M., Cronin, S., Zhang, Z., Dresselhaus, M. S. and Mansfield, J. F., Phys. Rev. B 61, 2921 (2000)Google Scholar
6 Mott, N. F. and Davis, E. A., Electronic Processes in Non-Crystalline Materials, Clarendon Press, Oxford (1979)Google Scholar
7 Dresselhaus, M. S., Prospects for Nanoscale Thermoelectricity, Presented at the 2005 fall meeting of the MRS, Boston, MA 2005 (1.1 in the present proceedings)Google Scholar
8 Heremans, J. P., Thrush, C. M. and Morelli, D. T., Phys. Rev. B 70 115334 (2004)Google Scholar
9 Cullity, B. D., Elements of X-ray Diffraction, Addison-Wesley, Reading, MA (1956)Google Scholar
10 Heremans, J. P., Thrush, C. M. and Morelli, D. T., J. Appl. Phys. 98 063703 (2005)Google Scholar
11 Guinier, A., Nature 142 569 (1938)Google Scholar
12 Preston, G. D., Nature 142 570 (1938)Google Scholar
13 Lasbley, A., Granger, R. and Rolland, S., Solid State Commun. 13 1045–8 (1973)Google Scholar
14 Roberts, B. W., J. Phys. Chem. Ref. Data 5 581–821 (1976)Google Scholar
15 Hindley, N. K. and Watson, J. H. P., Phys. Rev. 183 525 (1969)Google Scholar
16 LaLevic, B., Phys. Lett. 16 206 (1965)Google Scholar
17 Tsidil'kovskii, I. M., Thermomagnetic Effects in Semiconductors, Academic Press, New York (1962)Google Scholar
18 Ravich, Yu. I., Efimova, B. A., and Smirnov, I. A., Semiconducting Lead Chalcogenides, Plenum Press, New York, (1970).Google Scholar
19 Chernik, A., Kaidanov, V. I., Vinogradova, M. I., and Kolomoets, N. V., Sov. Phys. Semicond. 2, 645 (1968).Google Scholar
20 Preier, H., Appl. Phys. 20 189 (1979).Google Scholar
21 Except perhaps Rayleigh scattering, which could result in λ = 4, but would apply only if electrons scattered on features much smaller than their de Broglie wavelength.Google Scholar
22 Vashaee, D. and Shakouri, A., Phys. Rev. Lett. 92, 106103 (2004).Google Scholar