Magnetic-Field Dependence of Thermoelectric Properties of Sintered Bi90Sb10 Alloy
- 145 Downloads
The magnetic-field dependence of the thermoelectric properties and dimensionless figure of merit (ZT) of a sintered Bi90Sb10 alloy were experimentally and theoretically evaluated. The Bi-Sb alloy was synthesized in a quartz ampule using the melting method, and the resultant ingot was then ground via ball milling. A sintered Bi90Sb10 alloy with a particle size in the range of several to several tens of micrometers was prepared using the spark plasma sintering (SPS) method. The magnetic-field dependence of the electrical resistivity, Seebeck coefficient, and thermal conductivity were experimentally evaluated at temperatures of 77–300 K for magnetic fields of up to 2.9 T. The results showed that ZT increased by 37% at 300 K under a 2.5-T magnetic field. A theoretical calculation of the magneto-Seebeck coefficient based on the Boltzmann equation with a relaxation time approximation was also performed. Hence, the experimental result for the magneto-Seebeck coefficient of the Bi90Sb10 alloy at 300 K was qualitatively and quantitatively explained. Specifically, the carrier scattering mechanism was shown to be acoustic phonon potential scattering and the carrier mobility ratio between the L- and T-points was found to be 3.3, which corresponds to the characteristics of a single crystal. It was concluded that the effect of the magnetic field on the Seebeck coefficient was demonstrated accurately using the theoretical calculation model.
KeywordsBi-Sb alloy thermoelectrics magneto-Seebeck effect Boltzmann equation
Unable to display preview. Download preview PDF.
The author would like to thank Mr. Ryoei Homma of Saitama University and Mr. Masaru Kunii and Mr. Hirotaka Nishiate of AIST for their assistance with this research. This research was supported in part by JSPS KAKENHI (Grant numbers: 26886016 and 15H04142) and the Inamori Foundation, Izumi Science and Technology Foundation.
- 5.H. Scherrer and S. Scherrer, Thermoelectrics Handbook: Macro to Nano, ed. D.M. Rowe (Boca Raton, FL: CRC, 2006), p. 27.Google Scholar
- 6.M.V. Vedernikov and V.L. Kuznetsov, CRC Handbook of Thermoelectrics, ed. D.M. Rowe (Boca Raton, FL: CRC, 1995), p. 609.Google Scholar
- 9.V.M. Grabov and O.N. Uryupin, Thermoelectrics Handbook: Macro to Nano, ed. D.M. Rowe (Boca Raton, FL: CRC, 2006), p. 28.Google Scholar
- 13.T. Komine, Y. Ishikawa, A. Suzuki, H. Shirai, and Y. Hasegawa, Proceedings of 22nd International Conference on Thermoelectrics, p. 500 (2003).Google Scholar
- 16.E.E. Mendez, Ph.D. thesis, Massachusetts Institute of Technology (1979).Google Scholar
- 18.W.P. Lin, D.E. Wesolowski, and C.C. Lee, J. Mater. Sci. 22, 1313 (2011).Google Scholar
- 23.C. Kittel, Introduction to Solid State Physics (New York: Wiley, 1966).Google Scholar
- 27.B.S. Farag and S. Tanuma, ISSP Technical Report, Ser. B No. 18 (1976)Google Scholar
- 32.Y.M. Lin, Master’s thesis, Massachusetts Institute of Technology (2000)Google Scholar
- 33.N.B. Brandt and S.M. Chudinov, Sov. Phys. JETP 32, 815 (1971).Google Scholar