Abstract
Nonstoichiometric ternary thermoelectric materials Ag0.84Sb1.15M0.01Te2.16 (M=Ce, Yb, Cu) were prepared by a direct melt-quench and hot press process. The carrier concentration of all the samples increased after doping. Thermoelectric properties, namely electrical conductivity, Seebeck coefficient, and thermal conductivity, were measured from 300 to 673 K. The phase transition occurring at about 418 K representing the phase transition from β-Ag2Te to α-Ag2Te influenced the electrical transport properties. The electrical conductivities of Ce and Yb doped samples increased after doping from 1.9×104 to 2.5×104 and 2.3×104 S·m−1, respectively, at 673 K. Also, at room temperature, the Seebeck coefficient of the Ce doped sample relatively increased corresponding to the high carrier concentration due to the changes in the band structure. However, all the thermal conductivities increased after doping at low temperature. Because of the higher thermal conductivity, the dimensionless figure of merit ZT of these doped samples has not been improved.
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References
D.M. Rowe, CRC Handbook of Thermoelectrics, CRC Press, Boca Raton, 1995, p.1.
T.M. Tritt, Thermoelectric materials: holey and unholey semiconductors, Science, 283(1999), p.804.
T.C. Harman, P.J. Taylor, M.P. Walsh, and B.E. LaForge, Quantum dot superlattice thermoelectric materials and devices, Science, 297(2002), p.2229.
I.U. Arachchige, J.S. Wu, V.P. Dravid, and M.G. Kanatzidis, Nanocrystals of the quaternary thermoelectric materials AgPbmSbTe m+2 (m=1–18) phase segregated or solid solutions, Adv. Mater., 20(2008), p.3638.
L.J. Wu, J.C. Zheng, J. Zhou, Q. Li, J.H. Yang, and Y.M. Zhu, Nanostructures and defects in thermoelectric AgPb18SbTe20 single crystal, J. Appl. Phys., 105(2009), art. No.094317.
A. Gueguen, P.F.P. Poudeu, C.P. Li, S. Moses, C. Uher, J. He, V. Dravid, K.M. Paraskevopoulos, and M.G. Kanatzidis, Thermoelectric properties and nanostructuring in the p-type materials NaPb18−x SnxMTe (M=Sb, Bi), Chem. Mater., 21(2009), p.1683.
S.H. Yang, T.J. Zhu, T. Sun, S.N. Zhang, X.B. Zhao, and J. He, Nanostructures in high-performance (GeTe)x(AgSbTe2)100−x thermoelectric materials, Nanotechnology, 19(2008), art. No.245707.
K.F. Hsu, S. Loo, F. Guo, W. Chen, J.S. Dyck, C. Uher, T. Hogan, E.K. Polychroniadis, and M.G. Kanatzidis, Cubic AgPbmSbTe2+m : bulk thermoelectric materials with high figure of merit, Science, 303(2004), p.818.
E.A. Skrabek and D.S. Trimmer, Properties of the general TAGS system, [in] D.M. Rowe ed. CRC Handbook of Thermoelectrics, CRC Press, Boca Raton, 1995, p.267.
H. Matsushita, E. Hagiwara, and A. Katsui, Phase diagram and thermoelectric properties of Ag3−x Sb1+x Te4 system, J. Mater. Sci., 39(2004), p.6299.
R.G. Maier, Zur kenntnis des systems PbTe-AgSbTe2, Z. Metallkd., 54(1963), p.311.
R.M. Marin, G. Brun, and J.C. Tedenac, Phase equilibria in the Sb2Te3-Ag2Te system, J. Mater. Sci., 20(1985), p.730.
R. Wolfe, J.H. Wernick, and S.E. Haszko, Anomalous hall effect in AgSbTe2, J. Appl. Phys., 31(1959), p.1959.
F.D. Rosi, E.F. Hockings, and N.E. Lindenblad, Semiconducting materials for thermoelectric power generation, RCA Rev., 22(1961), p.82.
D.T. Morelli, V. Jovovic, and J.P. Heremans, Intrinsically minimal thermal conductivity in cubic I-V-VI2 semiconductors, Phys. Rev. Lett., 101(2008), art. No.035901.
S.N. Zhang, T.J. Zhu, S.H. Yang, C. Yu, and X.B. Zhao, Phase compositions, nanoscale microstructures and thermoelectric properties in Ag2−y SbyTe1+y alloys with precipitated Sb2Te3 plates, Acta Mater., 58(2010), p.4160.
E. Quarez, K.F. Hsu, R. Pcionek, N. Frangis, N.K. Polychroniadis, and M.G. Kanatzidis, Nanostructuring, compositional fluctuations, and atomic ordering in the thermoelectric materials AgPbmSbTe2+m: The myth of solid solutions, J. Am. Chem. Soc., 127(2005), p.9177.
H. Wang, J.F. Li, M. Zou, and T. Sui, Synthesis and transport property of AgSbTe2 as a promising thermoelectric compound, Appl. Phys. Lett., 93(2008), art. No.202106.
V. Jovovic and J.P. Heremans, Measurements of the energy band gap and valence band structure of AgSbTe2, Phys. Rev. B, 77(2008), art. No.245204.
L.H. Ye, K. Hoang, A.J. Freeman, S.D. Mahanti, J. He, T.M. Tritt, and M.G. Kanatzidis, First-principles study of the electronic, optical, and lattice vibrational properties of AgSbTe2, Phys. Rev. B, 77(2008), art. No.245203.
S.N. Zhang, T.J. Zhu, S.H. Yang, C. Yu, and X.B. Zhao, Improved thermoelectric properties of AgSbTe2 based compounds with nanoscale Ag2Te in situ precipitates, J. Alloys Compd., 499(2010), p.215.
P.F. Taylor and C. Wood, Thermoelectric properties of Ag2Te, J. Appl. Phys., 32(1961), p.1.
A. Ishida, D. Cao, S. Morioka, M. Veis, Y. Inoue, and T. Kita, Enhanced Seebeck coefficient in EuTe/PbTe [100] short-period superlattices, Appl. Phys. Lett., 92(2008), art. No.182105.
G.S. Nolas, J. Sharp, and H.J. Goldsmid, Thermoelectrics: Basic principles and new materials developments, [in] R. Hull and R.M. Osgood eds. Basic Principles and New Materials Developments Thermoelectrics, Springer, New York, 2001, p.292.
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This work was financially supported by the National High-Tech Research and Development Program of China (No.2007AA03Z234), the Major State Basic Research and Development Program of China (No.2007CB607502), and the National Natural Science Foundation of China (No.50731006).
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Zhang, Sn., Jiang, Gy., Zhu, Tj. et al. Doping effect on thermoelectric properties of nonstoichiometric AgSbTe2 compounds. Int J Miner Metall Mater 18, 352–356 (2011). https://doi.org/10.1007/s12613-011-0446-5
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DOI: https://doi.org/10.1007/s12613-011-0446-5