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Improving the thermoelectric figure of merit

The efficiency of a thermoelectric generator and the coefficient of performance (COP) of a thermoelectric heat pump are related to the hot and cold junction temperatures and a quantity known as the figure of merit, zT. During the second half of the twentieth century the figure of merit has gradually...

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Autor principal: Goldsmid, H. Julian
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Taylor & Francis 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8049463/
https://www.ncbi.nlm.nih.gov/pubmed/33907527
http://dx.doi.org/10.1080/14686996.2021.1903816
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author Goldsmid, H. Julian
author_facet Goldsmid, H. Julian
author_sort Goldsmid, H. Julian
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description The efficiency of a thermoelectric generator and the coefficient of performance (COP) of a thermoelectric heat pump are related to the hot and cold junction temperatures and a quantity known as the figure of merit, zT. During the second half of the twentieth century the figure of merit has gradually improved. This has come about through the selection of semiconducting materials with improved electronic properties and a small lattice thermal conductivity. Further advancements have been achieved by enhancing the scattering of phonons. There is also the possibility of improving the so-called power factor, that is the part of the figure of merit that contains the Seebeck coefficient and the electrical conductivity. However, it appears that it will be increasingly difficult to make further advances because of the manner in which these quantities vary with the Fermi energy. It is shown that this may set a practical limit on zT. Nevertheless, it may be possible to reach an efficiency or COP of about 40% of that of an ideal thermodynamic machine.
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spelling pubmed-80494632021-04-26 Improving the thermoelectric figure of merit Goldsmid, H. Julian Sci Technol Adv Mater Focus on Thermoelectric Materials The efficiency of a thermoelectric generator and the coefficient of performance (COP) of a thermoelectric heat pump are related to the hot and cold junction temperatures and a quantity known as the figure of merit, zT. During the second half of the twentieth century the figure of merit has gradually improved. This has come about through the selection of semiconducting materials with improved electronic properties and a small lattice thermal conductivity. Further advancements have been achieved by enhancing the scattering of phonons. There is also the possibility of improving the so-called power factor, that is the part of the figure of merit that contains the Seebeck coefficient and the electrical conductivity. However, it appears that it will be increasingly difficult to make further advances because of the manner in which these quantities vary with the Fermi energy. It is shown that this may set a practical limit on zT. Nevertheless, it may be possible to reach an efficiency or COP of about 40% of that of an ideal thermodynamic machine. Taylor & Francis 2021-04-13 /pmc/articles/PMC8049463/ /pubmed/33907527 http://dx.doi.org/10.1080/14686996.2021.1903816 Text en © 2021 The Author(s). Published by National Institute for Materials Science in partnership with Taylor & Francis Group. https://creativecommons.org/licenses/by/4.0/This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Focus on Thermoelectric Materials
Goldsmid, H. Julian
Improving the thermoelectric figure of merit
title Improving the thermoelectric figure of merit
title_full Improving the thermoelectric figure of merit
title_fullStr Improving the thermoelectric figure of merit
title_full_unstemmed Improving the thermoelectric figure of merit
title_short Improving the thermoelectric figure of merit
title_sort improving the thermoelectric figure of merit
topic Focus on Thermoelectric Materials
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8049463/
https://www.ncbi.nlm.nih.gov/pubmed/33907527
http://dx.doi.org/10.1080/14686996.2021.1903816
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