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Microstructures and nanostructures in long-term annealed AgPb18SbTe20 (LAST-18) compounds and their influence on the thermoelectric properties

Published online by Cambridge University Press:  05 August 2011

Jayaram Dadda ,
Eckhard Müller ,
Susanne Perlt ,
Thomas Höche ,
Paula Bauer Pereira  and
Raphaël P. Hermann
Jayaram Dadda*
Affiliation:
Institute of Materials Research, German Aerospace Center (DLR), D-51170 Köln, Germany
Eckhard Müller
Affiliation:
Institute of Materials Research, German Aerospace Center (DLR), D-51170 Köln, Germany
Susanne Perlt
Affiliation:
Leibniz Institute of Surface Modification (IOM), D-04318 Leipzig, Germany
Thomas Höche
Affiliation:
Leibniz Institute of Surface Modification (IOM), D-04318 Leipzig, Germany
Paula Bauer Pereira
Affiliation:
Forschungszentrum Jülich GmbH, IFF, JNCS and JARA-FIT, D-52425 Jülich, GermanyFaculty of Sciences, University of Liège, B-4000 Liège, Belgium
Raphaël P. Hermann
Affiliation:
Forschungszentrum Jülich GmbH, IFF, JNCS and JARA-FIT, D-52425 Jülich, GermanyFaculty of Sciences, University of Liège, B-4000 Liège, Belgium
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

This article reports on the role of annealing on the development of microstructure and its concomitant effects on the thermoelectric properties of polycrystalline AgPbmSbTe2+m (m = 18, lead–antimony–silver–tellurium, LAST-18) compounds. The annealing temperature was varied by applying a gradient annealing method, where a 40-mm-long sample rod was heat treated in an axial temperature gradient spanning between 200 and 600 °C for 7 days. Transmission electron microscopy investigations revealed Ag2Te nanoparticles at a size of 20–250 nm in the matrix. A remarkable reduction in the thermal conductivity to as low as 0.8 W/mK was also recorded. The low thermal conductivity coupled with a large Seebeck coefficient of ∼320 μV/K led to high ZT of about 1.05 at 425 °C for the sample annealed at 505 °C. These results also demonstrate that samples annealed above 450 °C for long term are more thermally stable than those treated at lower temperatures.

Keywords

ThermoelectricityAnnealingSecond phases
Type
Articles
Information
Journal of Materials Research , Volume 26 , Issue 15: Focus Issue: Advances in Thermoelectric Materials , 14 August 2011 , pp. 1800 - 1812
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1.Bell, L.E.: Cooling, heating, generating power and recovering waste heat with thermoelectric systems. Science 321, 1457 (2008).CrossRefGoogle ScholarPubMed
2.Hachiuma, H. and Fukuda, K.: Activities and future vision of Komatsu thermo modules, in Proceedings of the Fifth European Conference on Thermoelectrics, Paper 01, September 10–12, 2007, p. 1.Google Scholar
3.Zhou, M., Li, J-F., and Kita, T.: Nanostructured AgPbmSbTem +2 system bulk materials with enhanced thermoelectric performance. J. Am. Chem. Soc. 130, 4527 (2008).CrossRefGoogle ScholarPubMed
4.Hsu, K.F., Loo, S., Guo, F., Chen, W., Dyck, J.S., Uher, C., Hogan, T., Polychroniadis, E.K., and Kanatzidis, M.G.: Cubic AgPbmSbTe2+m: Bulk thermoelectric materials with high figure of merit. Science 303, 818 (2004).CrossRefGoogle ScholarPubMed
5.Quarez, E., Hsu, K.F., Pcionek, R., Frangis, N., Polychroniadis, E.K., and Kanatzidis, M.G.: Nanostructuring, compositional fluctuations, and atomic ordering in the thermoelectric materials AgPbmSbTe2+m. The myth of solid solutions. J. Am. Chem. Soc. 127, 9177 (2005).CrossRefGoogle ScholarPubMed
6.Cook, B.A., Kramer, M.J., Harringa, J.L., Han, M-K., Chung, D-Y., and Kanatzidis, M.G.: Analysis of nanostructuring in high figure-of-merit Ag1-xPbmSbTe2+m thermoelectric materials. Adv. Funct. Mater. 19, 1254 (2009).CrossRefGoogle Scholar
7.Kanatzidis, M.: Nanostructured thermoelectrics: The new paradigm? Chem. Mater. 22, 648 (2010).CrossRefGoogle Scholar
8.Vineis, C.J., Shakouri, A., Majumdar, A., and Kanatzidis, M.G.: Nanostructured thermoelectrics: Big efficiency gains from small features. Adv. Mater. 22, 3970 (2010).CrossRefGoogle ScholarPubMed
9.Kosuga, A., Uno, M., Kurosaki, K., and Yamanaka, S.: Thermoelectric properties of Ag1-xPb18SbTe20 (x = 0, 0.1, 0.3). J. Alloy. Comp. 387, 52 (2005).CrossRefGoogle Scholar
10.Chen, N., Gascoin, F., Snyder, G.J., Mueller, E., Karpinski, G., and Stiewe, C.: Macroscopic thermoelectric inhomogeneities in (AgSbTe2)x (PbTe)1-x. Appl. Phys. Lett. 87, 171903 (2005).CrossRefGoogle Scholar
11.Yan, Y., Tang, X., Liu, H., Yin, L., and Zhang, Q.: Cooling rate dependence of microstructure and thermoelectric properties of AgPb18SbTe20 compound, in Proceedings of the International Conference on Thermoelectrics, Jeju Island, Korea, 2007, pp. 61–63.Google Scholar
12.Sootsman, J., Pcionek, R., Kong, H., Uher, C., and Kanatzidis, M.G.: Phase segregation and thermoelectric properties of AgPbmSbTe2+m (m = 2, 4, 6 and 8). Mater. Res. Soc. Symp. 886, 0886–F08-05.1 (2006).Google Scholar
13.Sootsman, J.R., Pcionek, R.J., Kong, H., Uher, C., and Kanatzidis, M.G.: Strong reduction of thermal conductivity in nanostructured PbTe prepared by matrix encapsulation. Chem. Mater. 18, 4993 (2006).CrossRefGoogle Scholar
14.Bilc, D.I., Mahanti, S.D., and Kanatzidis, M.G.: Electronic transport properties of PbTe and AgPbmSbTe2+m systems. Phys. Rev. B 74, 125202 (2006).CrossRefGoogle Scholar
15.Hazama, H., Mizutani, U., and Asahi, R.: First-principles calculations of Ag-Sb nanodot formation in thermoelectric AgPbmSbTe2+m (m = 6, 14, 30). Phys. Rev. B 73, 115108 (2006).CrossRefGoogle Scholar
16.Rodriguez-Carvajal, J.: FULLPROF: A program for Rietveld refinement and pattern matching analysis. Abs. Sat. Meet Powder Diff. XV Cong. IUCr, Toulouse, France, 1990, p. 127.Google Scholar
17.Migliori, A., Sarrao, J.L., Visscher, W.M., Bell, T.M., Lei, M., Fisk, Z., and Leisure, R.G.: Resonant ultrasound spectroscopic techniques for measurement of the elastic moduli of solids. Physica B 183, 1 (1993).CrossRefGoogle Scholar
18.ANSYS Academic Research Release 11.0 Product Documentation, Help System, Thermal Analysis Guide, Chapter 2. Steady State Thermal Analysis (ANSYS, Inc., 2007), p. 11.Google Scholar
19.Gierlotka, W., £apsa, J., and Fitzner, K.: Thermodynamic description of the Ag–Pb–Te ternary system. J. Phase Equilib. Diffus. 31, 509 (2010).CrossRefGoogle Scholar
20.Henger, G.W. and Peretti, E.A.: Constitution diagram for the PbTe-Sb system. J. Chem. Eng. Data 10, 16 (1965).CrossRefGoogle Scholar
21.Lee, B-Z., Oh, C-S., and Lee, D.N.: A thermodynamic evaluation of the Ag–Pb–Sb system. J. Alloy. Comp. 215, 293 (1994).Google Scholar
22.Sharov, M.K.: Silver solubility in PbTe crystals. Inorg. Mater. 44, 569 (2008).CrossRefGoogle Scholar
23.Dow, H.S., Oh, M.W., Kim, B.S., Park, S.D., Min, B.K., Lee, H.W., and Wee, D.M.: Effect of Ag or Sb additions on the thermoelectric properties of PbTe. J. Appl. Phys. 108, 113709 (2010).CrossRefGoogle Scholar
24.Blachnik, R. and Gather, B.: Mischungen von GeTe, SnTe und PbTe mit Ag2Te – Ein Beitrag zur Klärung der Konstitution der ternären Ag-IVb-Te Systeme (IVb = Ge, Sn, Pb). J. Less-Common Met. 60, 25 (1987).CrossRefGoogle Scholar
25.Sugar, J.D. and Medlin, D.L.: Precipitation of Ag2Te in the thermoelectric material AgSbTe2. J. Alloy. Comp. 478, 75 (2009).CrossRefGoogle Scholar
26.Ikeda, T., Ravi, V.A., and Snyder, G.J.: Microstructure size control through cooling rate in thermoelectric PbTe–Sb2Te3 composites. Metall. Mater. Trans. A 41, 641 (2010).CrossRefGoogle Scholar
27.Maier, R.G.: Zur Kenntnis des Systems PbTe–AgSbTe2. Z. Metallk. 54, 311 (1963).Google Scholar
28.Barabash, S.V., Ozolins, V., and Wolverton, C.: First-principles theory of competing order types, phase separation, and phonon spectra in thermoelectric AgPbmSbTe2+m alloys. Phys. Rev. Lett. 101, 155704 (2008).CrossRefGoogle ScholarPubMed
29.Wada, K., Suzuki, A., Sato, H., and Kikuchi, R.: Soret effect in solids. J. Phys. Chem. Solids 46, 1195 (1985).CrossRefGoogle Scholar
30.Manolikas, C.: A study by means of electron microscopy and electron diffraction of the phase transformation and the domain structure in Ag2Te. J. Solid State Chem. 66, 1 (1987).CrossRefGoogle Scholar
31.Lensch-Falk, J.L., Sugar, J.D., Hekmaty, M.A., and Medlin, D.L.: Morphological evolution of Ag2Te precipitates in thermoelectric PbTe. J. Alloy. Comp. 504, 37 (2010).CrossRefGoogle Scholar
32.Das, V.D. and Karunakaran, D.: Thickness dependence of the phase transition temperature in Ag2Te thin films. J. Phys. Chem. Solids 46, 551 (1985).CrossRefGoogle Scholar
33.Aliev, F.F.: Electrical and thermoelectric properties of p-Ag2Te in the β phase. Semiconductors 37, 1057 (2003).CrossRefGoogle Scholar
34.Ren, F., Case, E.D., Ni, J.E., Timm, E.J., Lara-Curzio, E., Trejo, R.M., Lin, C.H., and Kanatzidis, M.G.: Temperature-dependent elastic moduli of lead telluride-based thermoelectric materials. Philos. Mag. Lett. 89, 143 (2009).CrossRefGoogle Scholar
35.Allgaier, R.S. and Scanlon, W.W.: Mobility of electrons and holes in PbS, PbSe, and PbTe between room temperature and 4.2 °K. Phys. Rev. 111, 1029 (1958).CrossRefGoogle Scholar
36.Pei, Y., Lensch-Falk, J., Toberer, E.S., Medlin, D.L., and Snyder, G.J.: High thermoelectric performance in PbTe due to large nanoscale Ag2Te precipitates and La doping. Adv. Funct. Mater. 21, 241 (2011).CrossRefGoogle Scholar
37.Strauss, A.J.: Effect of Pb- and Te-saturation on carrier concentrations in impurity-doped PbTe. J. Electron. Mater. 2, 553 (1973).CrossRefGoogle Scholar
38.Rowe, D.M.: Thermoelectrics Handbook, 2nd ed. (CRC Press, Taylor & Francis Group, USA, 2006), pp. 1–16.Google Scholar