Abstract
Bipolar carrier transport is often a limiting factor in the thermoelectric efficiency of narrow bandgap materials at high temperatures due to the reduction in the Seebeck coefficient and the introduction of an additional term to the thermal conductivity. Using the Boltzmann transport formalism and a two-band model, we simulate transport through bipolar systems and calculate their thermoelectric transport properties: the electrical conductivity, the Seebeck coefficient and the thermoelectric power factor. We present an investigation into the doping optimisation of such materials, showing the detrimental impact that rising temperatures have if the doping (and the Fermi level) is not optimised for each operating temperature. We also show that the doping levels for optimized power factors at a given operating temperature differ in bipolar systems compared to unipolar ones. We show finally that at 600 K, in a bipolar material with bandgap approximately that of Bi2Te3, the optimal doping required can reside between 10% and 30% larger than that required for an optimal unipolar material depending on the electronic scattering details of the material.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
G. Prashun, S. Vladan, and E.S. Toberer, Nat. Rev. Mater. 2, 17053 (2017).
L.-D. Zhao, H.J. Wu, S.Q. Hao, C.I. Wu, X.Y. Zhou, K. Biswas, J.Q. He, T.P. Hogan, C. Uher, C. Wolverton, V.P. Dravid, and M.G. Kanatzidis, Energy Environ. Sci. 6, 3346 (2013).
H. Goldsmid, Materials 7, 2577 (2014).
L.-D. Zhao, V.P. Dravid, and M.G. Kanatzidis, Energy Environ. Sci. 7, 251 (2014).
M. Lundstrom, Notes on Bipolar Thermal Conductivity (2017). https://nanohub.org/groups/ece656_f17/File:Notes_on_Bipolar_Thermal_Conductivity.pdf. Accessed 11 June 2018.
M. Thesberg, H. Kosina, and N. Neophytou, Phys. Rev. B 95, 125206 (2017).
G. Snyder and E. Toberer, Nat. Mater. 7, 105 (2008).
Q. Zhang, Q. Song, X. Wang, J. Sun, Q. Zhu, K. Dahal, X. Lin, F. Cao, J. Zhou, S. Chen, G. Chen, J. Mao, and Z. Ren, Energy Environ. Sci. 11, 933 (2018).
A.F. Ioffe, Semiconductor Thermoelements, and Thermoelectric Cooling (London: Infosearch Ltd., 1957).
P.G. Burke, B.M. Curtin, J.E. Bowers, and A.C. Gossard, Nano Energy 12, 735 (2015).
J.-H. Bahk and A. Shakouri, Phy. Rev. B 93, 165209 (2016).
H.-S. Kim, K.H. Lee, J. Yoo, W.H. Shin, J.W. Roh, J.-Y. Hwang, S.W. Kim, and S.I. Kim, J. Alloys Compd 741, 869 (2018).
L. Zhang, P. Xiao, L. Shi, G. Henkelman, J.B. Goodenough, and J. Zhou, J. Appl. Phys. 117, 155103 (2015).
B. Poudel, Q. Hao, Y. Ma, Y. Lan, A. Minnich, B. Yu, X. Yan, D. Wang, A. Muto, D. Vashaee, X. Chen, J. Liu, M.S. Dresselhaus, G. Chen, and Z. Ren, Science 320, 634 (2008).
G. Mahan and J.O. Sofo, Proc. Natl. Acad. Sci. USA 93, 7436 (1996).
T.J. Scheidemantel, C.A. Draxl, T. Thonhauser, J.V. Badding, and J.O. Sofo, Phys. Rev. B 68, 125210 (2003).
M. Lundstrom, Fundamentals of Carrier Transport (Cambridge: Cambridge University Press, 2000).
S. Foster, M. Thesberg, and N. Neophytou, Phys. Rev. B 96, 195425 (2017).
N. Neophytou and M. Thesberg, J. Comput. Electron. 15, 16 (2016).
C. Jeong, R. Kim, and M. Lundstrom, J. Appl. Phys. 111, 113707 (2012).
G. Tan, L.-D. Zhao, and M. Kanatzidis, Chem. Rev. 116, 12123 (2016).
Acknowledgments
This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme (Grant Agreement No. 678763).
Open Access
This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
About this article
Cite this article
Foster, S., Neophytou, N. Doping Optimization for the Power Factor of Bipolar Thermoelectric Materials. J. Electron. Mater. 48, 1889–1895 (2019). https://doi.org/10.1007/s11664-018-06857-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11664-018-06857-1