Hostname: page-component-5c6d5d7d68-xq9c7 Total loading time: 0 Render date: 2024-08-15T22:41:02.989Z Has data issue: false hasContentIssue false

Thermoelectric BehaVior of Conducting Polymers: On the Possibility of “Off-Diagonal” Thermoelectricity

Published online by Cambridge University Press:  15 February 2011

N. Mateeva
Affiliation:
TecOne, Inc., 1803 Sageway Drive, Tallahassee, FL 32303
H. Niculescu
Affiliation:
Also at The Florida A&, M Univ./Florida State Univ. College of Engineering.
J. Schlenoff
Affiliation:
Also at The Chemistry Department of Florida State Univ
L. Testardi
Affiliation:
TecOne, Inc., 1803 Sageway Drive, Tallahassee, FL 32303
Get access

Abstract

Non-cubic materials, when structurally aligned, possess sufficient anisotropy to exhibit thermoelectric effects where the electrical and thermal currents are orthogonal (“off-diagonal” thermoelectricity). We discuss the benefits of this form of thermoelectricity for devices and describe a search for suitable properties in the air-stable conducting polymers polyaniline and polypyrrole. We find the simple and general correlation that the logarithm of the electrical conductivity scales linearly with the Seebeck coefficient on doping but with proportionality in excess of the conventional prediction for thermoelectricity. The correlation is unexpected in its universality and unfavorable for thermoelectric applications. A simple model suggests that mobile charges of both signs exist in these polymers, and this leads to reduced thermoelectric efficiency. We also briefly discuss non air-stable polyacetylene, where “ambipolar” transport does not appear to occur, and where properties seem more favorable for thermoelectricity.

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. For a further discussion of the “off-diagonal” thermoelectric effects see “Physical Properties of Crystals”, Nye, J.F., Chapter XII, Clarendon Press, (1985). For references to recent experimental observations, see L. R. Testardi, Appl Phys- Lett., 64 2347 (1994)Google Scholar
2. Reynolds, J. R., Schlenoff, J. B., and Chien, C. W., J. Electrochem. Soc. 132, 1131 (1985).Google Scholar
3. See, for example, “Physical Properties of Polymers Handbook”, edited by James Mark, chapter 34 by Kohlman, R. S., Joo, J. and Epstein, A. J., American Institute of Physics, (1996).Google Scholar
4. Adams, P. L., Laughlin, J and Monkman, A P., Synth Met., 76, 157 (1996); A. P. Monkman, P. N. Adams, P. J. Laughlin and E. R. Holland, Synth. Met., 69, 183 (1995).Google Scholar
5. MacDiarmid, A. G., Chiang, J. C., Richter, A. F., Somasiri, N. L. D. and Epstein, A.J. in “Conducting Polymers”,Alcacer, L., Editor; Reidel.Dordrecht (Netherlands), 105 (1987).Google Scholar
6. See, for example, “Thermoelectricity: Science and Engineering”, edited by Heikes, R. and Ure, R, chapter II by Ure, R. W. and Heikes, R. R., Interscience Publishers, N.Y., (1961), and “CRC Handbook of Thermoelectrics”, edited by D. M. Rowe, chapter 5 by C M. Bhandari and D. M. Rowe, CRC Press, Boca Raton, (1995).Google Scholar
7. See, for example, “Electronic Processes in Noncrystalline Materials”, Mott, N. F. and Davis, E A., Oxford University Press, London, (1979).Google Scholar
8. See, for example, “Electronic Properties of Doped Semiconductors”, Shlkovskii, B I. and Efros, A- L.. Springer, Berlin, (1979).Google Scholar