Open Access System for Information Sharing

Login Library

 

Article
Cited 1 time in webofscience Cited 0 time in scopus
Metadata Downloads
Full metadata record
Files in This Item:
There are no files associated with this item.
DC FieldValueLanguage
dc.contributor.authorJIN, HYUNGYUko
dc.contributor.authorJoseph P. Heremansko
dc.date.accessioned2018-12-13T07:41:58Z-
dc.date.available2018-12-13T07:41:58Z-
dc.date.created2018-12-04-
dc.date.issued2018-11-
dc.identifier.citationPHYSICAL REVIEW MATERIALS, v.2, no.11-
dc.identifier.issn2475-9953-
dc.identifier.urihttp://oasis.postech.ac.kr/handle/2014.oak/94488-
dc.description.abstractBismuth-antimony (Bi100−xSbx) alloys have the highest thermoelectric figure of merit of all n-type thermoelectric materials below 200 K. They are the only Te-free thermoelectric alternatives to the tetradymite materials for applications at and below room temperature. Single-crystal Bi100−xSbx alloys show the maximum figure of merit zT∼0.5 at 200 K along the trigonal axis crystallographic direction, but the cost associated with single-crystal growth and the tendency of single crystals to cleave preclude their use. Mechanically robust polycrystalline Bi100−xSbx/Al2O3 nanocomposites are shown here to be able to reach competitive zT values. Two compositions are investigated, Bi82Sb18 and Bi88Sb12. Thermal and electrical transport properties confirm significant reduction of lattice thermal conductivity in the nanocomposite samples, but the concurrent loss of electrical conductivity leads to an unfavorable net effect on zT. In contrast, a large increase in thermopower is observed in the Bi82Sb18/Al2O3 nanocomposite system, which is attributed to a better optimized doping level. Accordingly, the zT of a Bi82Sb18/Al2O3 nanocomposite sample is shown to reach zT∼0.4 at 240 K, which rivals that of single crystals. Near room temperature, the zT of the nanocomposite sample is improved by ∼60% over that of the single-crystalline sample. Galvano- and thermomagnetic analysis suggests a strong effect of carrier concentration on the zT of Bi100−xSbx/Al2O3 nanocomposite samples.-
dc.description.abstractBismuth-antimony (Bi100-xSbx) alloys have the highest thermoelectric figure of merit of all n-type thermoelectric materials below 200 K. They are the only Te-free thermoelectric alternatives to the tetradymite materials for applications at and below room temperature. Single-crystal Bi100-xSbx alloys show the maximum figure of merit zT similar to 0.5 at 200 K along the trigonal axis crystallographic direction, but the cost associated with single-crystal growth and the tendency of single crystals to cleave preclude their use. Mechanically robust polycrystalline Bi100-xSbx/Al2O3 nanocomposites are shown here to be able to reach competitive zT values. Two compositions are investigated, Bi82Sb18 and Bi82Sb18. Thermal and electrical transport properties confirm significant reduction of lattice thermal conductivity in the nanocomposite samples, but the concurrent loss of electrical conductivity leads to an unfavorable net effect on zT T. In contrast, a large increase in thermopower is observed in the Bi82Sb18/Al2O3 nanocomposite system, which is attributed to a better optimized doping level. Accordingly, the zT of a Bi82Sb18/Al2O3 nanocomposite sample is shown to reach zT similar to 0.4 at 240 K, which rivals that of single crystals. Near room temperature, the zT of the nanocomposite sample is improved by similar to 60% over that of the single-crystalline sample. Galvano- and thermomagnetic analysis suggests a strong effect of carrier concentration on the zT of Bi100-xSbx/Al2O3 nanocomposite samples.-
dc.description.abstractBismuth-antimony (Bi100-xSbx) alloys have the highest thermoelectric figure of merit of all n-type thermoelectric materials below 200 K. They are the only Te-free thermoelectric alternatives to the tetradymite materials for applications at and below room temperature. Single-crystal Bi100-xSbx alloys show the maximum figure of merit zT similar to 0.5 at 200 K along the trigonal axis crystallographic direction, but the cost associated with single-crystal growth and the tendency of single crystals to cleave preclude their use. Mechanically robust polycrystalline Bi100-xSbx/Al2O3 nanocomposites are shown here to be able to reach competitive zT values. Two compositions are investigated, Bi82Sb18 and Bi82Sb18. Thermal and electrical transport properties confirm significant reduction of lattice thermal conductivity in the nanocomposite samples, but the concurrent loss of electrical conductivity leads to an unfavorable net effect on zT T. In contrast, a large increase in thermopower is observed in the Bi82Sb18/Al2O3 nanocomposite system, which is attributed to a better optimized doping level. Accordingly, the zT of a Bi82Sb18/Al2O3 nanocomposite sample is shown to reach zT similar to 0.4 at 240 K, which rivals that of single crystals. Near room temperature, the zT of the nanocomposite sample is improved by similar to 60% over that of the single-crystalline sample. Galvano- and thermomagnetic analysis suggests a strong effect of carrier concentration on the zT of Bi100-xSbx/Al2O3 nanocomposite samples.-
dc.languageEnglish-
dc.publisherAMER PHYSICAL SOC-
dc.titleOptimization of the figure of merit in Bi100-xSbx/Al2O3 nanocomposites-
dc.typeArticle-
dc.identifier.doi10.1103/PhysRevMaterials.2.115401-
dc.type.rimsART-
dc.contributor.localauthorJIN, HYUNGYU-
dc.contributor.nonIdAuthorJoseph P. Heremans-
dc.identifier.wosid000451341300011-
dc.date.tcdate2019-02-01-
dc.citation.number11-
dc.citation.titlePHYSICAL REVIEW MATERIALS-
dc.citation.volume2-
dc.description.journalClass1-
dc.description.wostc1-

qr_code

  • mendeley

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Related Researcher

Researcher

 JIN, HYUNGYU
Dept of Mechanical Enginrg
Read more

Views & Downloads

Browse