File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Orbital alignment for high performance thermoelectric YbCd2Sb2 alloys

TitleOrbital alignment for high performance thermoelectric YbCd2Sb2 alloys
Authors
KeywordsAlignment
Antimony compounds
Bismuth compounds
C (programming language)
Thermal conductivity
Issue Date2018
PublisherAmerican Chemical Society. The Journal's web site is located at http://pubs.acs.org/cm
Citation
Chemistry of Materials, 2018, v. 30 n. 15, p. 5339-5345 How to Cite?
AbstractAs a typical class of Zintl thermoelectrics, AB2C2 (A = Eu, Yb, Ba, Ca, Mg; B = Zn, Cd, Mg, and C = Sb, Bi) compounds have shown a superior thermoelectric performance, largely stemming from the existence of multiple transporting bands in both conduction types. Being similar to many III–V and elemental semiconductors, the transport of holes in AB2C2 Zintls usually involves multiple valence bands with extrema at the Brillouin zone center Γ. However, these valence bands, originating from different orbitals, are unnecessarily aligned in energy due to the crystal field splitting. Formation of solid solutions between constituent compounds having opposite arrangements in energy of band orbitals is believed to be particularly helpful for thermoelectric enhancements, because orbital alignment increases band degeneracy while alloy defects scatter phonons. These effects are simultaneously realized in this work, where the p orbitals of anions in YbCd2–xZnxSb2 alloys are well-aligned for maximizing the electronic performance, and meanwhile high-concentration Cd/Zn substitutions are introduced for minimizing the lattice thermal conductivity. As a result, a significantly enhanced thermoelectric figure of merit, zT ∼ 1.3, is achieved, being a record among AB2C2 Zintls in p-type. This work demonstrates not only YbCd2–xZnxSb2 alloys as efficient thermoelectrics but also orbital alignment as an effective strategy for advancing thermoelectrics.
Persistent Identifierhttp://hdl.handle.net/10722/272232
ISSN
2017 Impact Factor: 9.89
2015 SCImago Journal Rankings: 4.232

 

DC FieldValueLanguage
dc.contributor.authorWang, X-
dc.contributor.authorLi, J-
dc.contributor.authorWANG, C-
dc.contributor.authorZhou, B-
dc.contributor.authorZheng, L-
dc.contributor.authorGao, B-
dc.contributor.authorChen, Y-
dc.contributor.authorPei, Y-
dc.date.accessioned2019-07-20T10:38:16Z-
dc.date.available2019-07-20T10:38:16Z-
dc.date.issued2018-
dc.identifier.citationChemistry of Materials, 2018, v. 30 n. 15, p. 5339-5345-
dc.identifier.issn0897-4756-
dc.identifier.urihttp://hdl.handle.net/10722/272232-
dc.description.abstractAs a typical class of Zintl thermoelectrics, AB2C2 (A = Eu, Yb, Ba, Ca, Mg; B = Zn, Cd, Mg, and C = Sb, Bi) compounds have shown a superior thermoelectric performance, largely stemming from the existence of multiple transporting bands in both conduction types. Being similar to many III–V and elemental semiconductors, the transport of holes in AB2C2 Zintls usually involves multiple valence bands with extrema at the Brillouin zone center Γ. However, these valence bands, originating from different orbitals, are unnecessarily aligned in energy due to the crystal field splitting. Formation of solid solutions between constituent compounds having opposite arrangements in energy of band orbitals is believed to be particularly helpful for thermoelectric enhancements, because orbital alignment increases band degeneracy while alloy defects scatter phonons. These effects are simultaneously realized in this work, where the p orbitals of anions in YbCd2–xZnxSb2 alloys are well-aligned for maximizing the electronic performance, and meanwhile high-concentration Cd/Zn substitutions are introduced for minimizing the lattice thermal conductivity. As a result, a significantly enhanced thermoelectric figure of merit, zT ∼ 1.3, is achieved, being a record among AB2C2 Zintls in p-type. This work demonstrates not only YbCd2–xZnxSb2 alloys as efficient thermoelectrics but also orbital alignment as an effective strategy for advancing thermoelectrics.-
dc.languageeng-
dc.publisherAmerican Chemical Society. The Journal's web site is located at http://pubs.acs.org/cm-
dc.relation.ispartofChemistry of Materials-
dc.rightsThis document is the Accepted Manuscript version of a Published Work that appeared in final form in [JournalTitle], copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see [insert ACS Articles on Request author-directed link to Published Work, see http://pubs.acs.org/page/policy/articlesonrequest/index.html].-
dc.subjectAlignment-
dc.subjectAntimony compounds-
dc.subjectBismuth compounds-
dc.subjectC (programming language)-
dc.subjectThermal conductivity-
dc.titleOrbital alignment for high performance thermoelectric YbCd2Sb2 alloys-
dc.typeArticle-
dc.identifier.emailChen, Y: yuechen@hku.hk-
dc.identifier.authorityChen, Y=rp01925-
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1021/acs.chemmater.8b02155-
dc.identifier.scopuseid_2-s2.0-85049844445-
dc.identifier.hkuros298941-
dc.identifier.volume30-
dc.identifier.issue15-
dc.identifier.spage5339-
dc.identifier.epage5345-
dc.publisher.placeUnited States-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats