Journal article
Semi-metallic polymers
Linköping University1
University of South Australia2
Vrije Universiteit Brussel3
Universite de Mons4
Norwegian University of Science and Technology5
Department of Energy Conversion and Storage, Technical University of Denmark6
Imaging and Structural Analysis, Department of Energy Conversion and Storage, Technical University of Denmark7
Polymers are lightweight, flexible, solution-processable materials that are promising for low-cost printed electronics as well as for mass-produced and large-area applications. Previous studies demonstrated that they can possess insulating, semiconducting or metallic properties; here we report that polymers can also be semi-metallic.
Semi-metals, exemplified by bismuth, graphite and telluride alloys, have no energy bandgap and a very low density of states at the Fermi level. Furthermore, they typically have a higher Seebeck coefficient and lower thermal conductivities compared with metals, thus being suitable for thermoelectric applications.
We measure the thermoelectric properties of various poly( 3,4-ethylenedioxythiophene) samples, and observe a marked increase in the Seebeck coefficient when the electrical conductivity is enhanced through molecular organization. This initiates the transition from a Fermi glass to a semi-metal. The high Seebeck value, the metallic conductivity at room temperature and the absence of unpaired electron spins makes polymer semi-metals attractive for thermoelectrics and spintronics.
Language: | English |
---|---|
Publisher: | Nature Publishing Group |
Year: | 2014 |
Pages: | 190-194 |
ISSN: | 14764660 and 14761122 |
Types: | Journal article |
DOI: | 10.1038/nmat3824 |
ORCIDs: | Andreasen, Jens Wenzel |
Bismuth alloys CHEMISTRY, ELECTRICAL-CONDUCTIVITY Electric properties Electrical conductivity FERMI GLASS Glass transition HIGHLY CONDUCTING POLYANILINE HOPPING TRANSPORT MATERIALS METAL TRANSITION Metallic conductivity Metallic properties Molecular organization PEDOT PHYSICS, POLY(3,4-ETHYLENEDIOXYTHIOPHENE) POLYTHIOPHENE Poly-3 ,4-ethylenedioxythiophene Polymers Printed electronics Seebeck coefficient Semiconducting polymers THIN-FILMS Thermal conductivity Thermoelectric application Thermoelectric properties Thermoelectricity VAPOR-PHASE POLYMERIZATION