Lattice strain and band overlap of the thermoelectric composite Mg2Si1-xSnx

Yao, W; Hu, S; Jia, F; Reimers, JR; Wang, Y; Singh, DJ; Ren, W

Lattice strain and band overlap of the thermoelectric composite Mg2Si1-xSnx

Yao, W Hu, S Jia, F Reimers, JR Wang, Y Singh, DJ Ren, W

Permalink

Publisher:: AMER PHYSICAL SOC
Publication Type:: Journal Article
Citation:: Physical Review B, 2022, 106, (10)
Issue Date:: 2022-09-01

Open Access

Copyright Clearance Process

Recently Added
In Progress
Open Access

This item is open access.

Adobe PDF

Download Accepted versionAdobe PDF (1.08 MB)

View on publisher's site

View statistics

Full metadata record

Field	Value	Language
dc.contributor.author	Yao, W
dc.contributor.author	Hu, S
dc.contributor.author	Jia, F
dc.contributor.author	Reimers, JR
dc.contributor.author	Wang, Y
dc.contributor.author	Singh, DJ
dc.contributor.author	Ren, W
dc.date.accessioned	2022-11-18T07:35:24Z
dc.date.available	2022-11-18T07:35:24Z
dc.date.issued	2022-09-01
dc.identifier.citation	Physical Review B, 2022, 106, (10)
dc.identifier.issn	2469-9950
dc.identifier.issn	2469-9969
dc.identifier.uri	http://hdl.handle.net/10453/163589
dc.description.abstract	Mg2Si1-xSnx solid solutions show enhanced thermoelectric performance when the Sn mole fraction x is approximately x=0.7. This has been discussed in terms of complexity of the electronic structure arising from the crossover of two bottom conduction bands, but direct detailed understanding of the origins and the precise nature of this band convergence is limited. Here, we report first-principles calculations of the band edge changes analyzed by band unfolding and crystal orbital Hamilton population techniques. We find that strain is particularly important at this crossing. Mg2Si and Mg2Sn show opposite trends in the conduction band edge shifts leading to a band crossover at x∼0.625. However, there are also important effects due to disorder. Transport calculations show that enhancement of the figure of merit ZT value owes to the combined effects of lattice strain, band edge overlap, composition change, and disorder.
dc.language	English
dc.publisher	AMER PHYSICAL SOC
dc.relation.ispartof	Physical Review B
dc.relation.isbasedon	10.1103/PhysRevB.106.104303
dc.rights	info:eu-repo/semantics/openAccess
dc.rights	Wenliang Yao, Shunbo Hu, Fanhao Jia, Jeffrey R. Reimers, Yin Wang, David J. Singh, and Wei Ren, Physical Review B, 106, 104303, 2022. "Copyright 2022 by the American Physical Society."
dc.subject	02 Physical Sciences, 03 Chemical Sciences, 09 Engineering
dc.subject.classification	Fluids & Plasmas
dc.title	Lattice strain and band overlap of the thermoelectric composite Mg2Si1-xSnx
dc.type	Journal Article
utslib.citation.volume	106
utslib.for	02 Physical Sciences
utslib.for	03 Chemical Sciences
utslib.for	09 Engineering
pubs.organisational-group	/University of Technology Sydney
pubs.organisational-group	/University of Technology Sydney/Faculty of Science
pubs.organisational-group	/University of Technology Sydney/Faculty of Science/School of Mathematical and Physical Sciences
utslib.copyright.status	open_access	*
dc.date.updated	2022-11-18T07:35:18Z
pubs.issue	10
pubs.publication-status	Published
pubs.volume	106
utslib.citation.issue	10

Abstract:

Mg2Si1-xSnx solid solutions show enhanced thermoelectric performance when the Sn mole fraction x is approximately x=0.7. This has been discussed in terms of complexity of the electronic structure arising from the crossover of two bottom conduction bands, but direct detailed understanding of the origins and the precise nature of this band convergence is limited. Here, we report first-principles calculations of the band edge changes analyzed by band unfolding and crystal orbital Hamilton population techniques. We find that strain is particularly important at this crossing. Mg2Si and Mg2Sn show opposite trends in the conduction band edge shifts leading to a band crossover at x∼0.625. However, there are also important effects due to disorder. Transport calculations show that enhancement of the figure of merit ZT value owes to the combined effects of lattice strain, band edge overlap, composition change, and disorder.

Please use this identifier to cite or link to this item:

http://hdl.handle.net/10453/163589