All-scale hierarchical thermoelectrics

MgTe in PbTe facilitates valence band convergence and suppresses bipolar thermal transport for high performance

L. D. Zhao, H. J. Wu, S. Q. Hao, C. I. Wu, X. Y. Zhou, K. Biswas, J. Q. He, T. P. Hogan, C. Uher, C. Wolverton, V. P. Dravid, Mercouri G Kanatzidis

Research output: Contribution to journalArticle

280 Citations (Scopus)

Abstract

We report a high ZT of ∼2.0 at 823 K for 2% Na-doped PbTe with 6% MgTe with excellent thermal stability. We attribute the high thermoelectric performance to a synergistic combination of enhanced power factor, reduction of the lattice thermal conductivity and simultaneous suppression of bipolar thermal conductivity. MgTe inclusion in PbTe owns triple functions: the Mg alloying within the solubility limit in PbTe modifies the valence band structure by pushing the two valence bands (L and Σ bands) closer in energy, thereby facilitating charge carrier injection. When the solubility limit of Mg is exceeded, ubiquitous endotaxial nanostructures form, which when coupled with mesoscale microstructuring results in a very low (lattice) thermal conductivity through all-scaled length phonon scattering. Meanwhile, most significantly, the Mg alloying enlarges the energy gap of conduction band (C band) and light valence band (L band), thereby suppresses the bipolar thermal conductivity through an increase in band gap.

Original languageEnglish
Pages (from-to)3346-3355
Number of pages10
JournalEnergy and Environmental Science
Volume6
Issue number11
DOIs
Publication statusPublished - Nov 2013

Fingerprint

Valence bands
thermal conductivity
Thermal conductivity
Alloying
solubility
Energy gap
Solubility
Phonon scattering
Conduction bands
Charge carriers
Band structure
energy
Nanostructures
Thermodynamic stability
scattering
Hot Temperature

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Environmental Chemistry
  • Pollution
  • Nuclear Energy and Engineering

Cite this

All-scale hierarchical thermoelectrics : MgTe in PbTe facilitates valence band convergence and suppresses bipolar thermal transport for high performance. / Zhao, L. D.; Wu, H. J.; Hao, S. Q.; Wu, C. I.; Zhou, X. Y.; Biswas, K.; He, J. Q.; Hogan, T. P.; Uher, C.; Wolverton, C.; Dravid, V. P.; Kanatzidis, Mercouri G.

In: Energy and Environmental Science, Vol. 6, No. 11, 11.2013, p. 3346-3355.

Research output: Contribution to journalArticle

Zhao, L. D. ; Wu, H. J. ; Hao, S. Q. ; Wu, C. I. ; Zhou, X. Y. ; Biswas, K. ; He, J. Q. ; Hogan, T. P. ; Uher, C. ; Wolverton, C. ; Dravid, V. P. ; Kanatzidis, Mercouri G. / All-scale hierarchical thermoelectrics : MgTe in PbTe facilitates valence band convergence and suppresses bipolar thermal transport for high performance. In: Energy and Environmental Science. 2013 ; Vol. 6, No. 11. pp. 3346-3355.
@article{ab4289e1754f4eb3a36d868f1d4a64bc,
title = "All-scale hierarchical thermoelectrics: MgTe in PbTe facilitates valence band convergence and suppresses bipolar thermal transport for high performance",
abstract = "We report a high ZT of ∼2.0 at 823 K for 2{\%} Na-doped PbTe with 6{\%} MgTe with excellent thermal stability. We attribute the high thermoelectric performance to a synergistic combination of enhanced power factor, reduction of the lattice thermal conductivity and simultaneous suppression of bipolar thermal conductivity. MgTe inclusion in PbTe owns triple functions: the Mg alloying within the solubility limit in PbTe modifies the valence band structure by pushing the two valence bands (L and Σ bands) closer in energy, thereby facilitating charge carrier injection. When the solubility limit of Mg is exceeded, ubiquitous endotaxial nanostructures form, which when coupled with mesoscale microstructuring results in a very low (lattice) thermal conductivity through all-scaled length phonon scattering. Meanwhile, most significantly, the Mg alloying enlarges the energy gap of conduction band (C band) and light valence band (L band), thereby suppresses the bipolar thermal conductivity through an increase in band gap.",
author = "Zhao, {L. D.} and Wu, {H. J.} and Hao, {S. Q.} and Wu, {C. I.} and Zhou, {X. Y.} and K. Biswas and He, {J. Q.} and Hogan, {T. P.} and C. Uher and C. Wolverton and Dravid, {V. P.} and Kanatzidis, {Mercouri G}",
year = "2013",
month = "11",
doi = "10.1039/c3ee42187b",
language = "English",
volume = "6",
pages = "3346--3355",
journal = "Energy and Environmental Science",
issn = "1754-5692",
publisher = "Royal Society of Chemistry",
number = "11",

}

TY - JOUR

T1 - All-scale hierarchical thermoelectrics

T2 - MgTe in PbTe facilitates valence band convergence and suppresses bipolar thermal transport for high performance

AU - Zhao, L. D.

AU - Wu, H. J.

AU - Hao, S. Q.

AU - Wu, C. I.

AU - Zhou, X. Y.

AU - Biswas, K.

AU - He, J. Q.

AU - Hogan, T. P.

AU - Uher, C.

AU - Wolverton, C.

AU - Dravid, V. P.

AU - Kanatzidis, Mercouri G

PY - 2013/11

Y1 - 2013/11

N2 - We report a high ZT of ∼2.0 at 823 K for 2% Na-doped PbTe with 6% MgTe with excellent thermal stability. We attribute the high thermoelectric performance to a synergistic combination of enhanced power factor, reduction of the lattice thermal conductivity and simultaneous suppression of bipolar thermal conductivity. MgTe inclusion in PbTe owns triple functions: the Mg alloying within the solubility limit in PbTe modifies the valence band structure by pushing the two valence bands (L and Σ bands) closer in energy, thereby facilitating charge carrier injection. When the solubility limit of Mg is exceeded, ubiquitous endotaxial nanostructures form, which when coupled with mesoscale microstructuring results in a very low (lattice) thermal conductivity through all-scaled length phonon scattering. Meanwhile, most significantly, the Mg alloying enlarges the energy gap of conduction band (C band) and light valence band (L band), thereby suppresses the bipolar thermal conductivity through an increase in band gap.

AB - We report a high ZT of ∼2.0 at 823 K for 2% Na-doped PbTe with 6% MgTe with excellent thermal stability. We attribute the high thermoelectric performance to a synergistic combination of enhanced power factor, reduction of the lattice thermal conductivity and simultaneous suppression of bipolar thermal conductivity. MgTe inclusion in PbTe owns triple functions: the Mg alloying within the solubility limit in PbTe modifies the valence band structure by pushing the two valence bands (L and Σ bands) closer in energy, thereby facilitating charge carrier injection. When the solubility limit of Mg is exceeded, ubiquitous endotaxial nanostructures form, which when coupled with mesoscale microstructuring results in a very low (lattice) thermal conductivity through all-scaled length phonon scattering. Meanwhile, most significantly, the Mg alloying enlarges the energy gap of conduction band (C band) and light valence band (L band), thereby suppresses the bipolar thermal conductivity through an increase in band gap.

UR - http://www.scopus.com/inward/record.url?scp=84885970937&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84885970937&partnerID=8YFLogxK

U2 - 10.1039/c3ee42187b

DO - 10.1039/c3ee42187b

M3 - Article

VL - 6

SP - 3346

EP - 3355

JO - Energy and Environmental Science

JF - Energy and Environmental Science

SN - 1754-5692

IS - 11

ER -