Spinodal decomposition and nucleation and growth as a means to bulk nanostructured thermoelectrics: Enhanced performance in Pb1-xSn xTe-PbS

John Androulakis, Chia Her Lin, Hun Jin Kong, Ctirad Uher, Chun I. Wu, Timothy Hogan, Bruce A. Cook, Thierry Caillat, Konstantinos M. Paraskevopoulos, Mercouri G Kanatzidis

Research output: Contribution to journalArticle

342 Citations (Scopus)

Abstract

The solid-state transformation phenomena of spinodal decomposition and nucleation and growth are presented as tools to create nanostructured thermoelectric materials with very low thermal conductivity and greatly enhanced figure of merit. The systems (PbTe)1-x(PbS)x and (Pb 0.95Sn0.05Te)1-x(PbS)x are not solid solutions but phase separate into PbTe-rich and PbS-rich regions to produce coherent nanoscale heterogeneities that severely depress the lattice thermal conductivity. For x gt; ∼0.03 the materials are ordered on three submicrometer length scales. Transmission electron microscopy reveals both spinodal decomposition and nucleation and growth phenomena the relative magnitude of which varies with x. We show that the (Pb0.95Sn 0.05Te)1-x(PbS)x system, despite its nanostructured nature, maintains a high electron mobility (> 100 cm 2/V·s at 700 K). At x ∼ 0.08 the material achieves a very low room-temperature lattice thermal conductivity of ∼0.4 W/m·K. This value is only 28% of the PbTe lattice thermal conductivity at room temperature. The inhibition of heat flow in this system is caused by nanostructure-induced acoustic impedance mismatch between the PbTe-rich and PbS-rich regions. As a result the thermoelectric properties of (Pb0.95Sn0.05Te) 1-x(PbS)x at x = 0.04, 0.08, and 0.16 were found to be superior to those of PbTe by almost a factor of 2. The relative importance of the two observed modes of nanostructuring, spinodal decomposition and nucleation and growth, in suppressing the thermal conductivity was assessed in this work, and we can conclude that the latter mode seems more effective in doing so. The promise of such a system for high efficiency is highlighted by a ZT ∼ 1.50 at 642 K for x ∼ 0.08.

Original languageEnglish
Pages (from-to)9780-9788
Number of pages9
JournalJournal of the American Chemical Society
Volume129
Issue number31
DOIs
Publication statusPublished - Aug 8 2007

Fingerprint

Thermal Conductivity
Spinodal decomposition
Thermal conductivity
Nucleation
Growth
Nanostructures
Temperature
Acoustic impedance
Electron mobility
Transmission Electron Microscopy
Electric Impedance
Acoustics
Solid solutions
Hot Temperature
Electrons
Heat transfer
Transmission electron microscopy

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Spinodal decomposition and nucleation and growth as a means to bulk nanostructured thermoelectrics : Enhanced performance in Pb1-xSn xTe-PbS. / Androulakis, John; Lin, Chia Her; Kong, Hun Jin; Uher, Ctirad; Wu, Chun I.; Hogan, Timothy; Cook, Bruce A.; Caillat, Thierry; Paraskevopoulos, Konstantinos M.; Kanatzidis, Mercouri G.

In: Journal of the American Chemical Society, Vol. 129, No. 31, 08.08.2007, p. 9780-9788.

Research output: Contribution to journalArticle

Androulakis, John ; Lin, Chia Her ; Kong, Hun Jin ; Uher, Ctirad ; Wu, Chun I. ; Hogan, Timothy ; Cook, Bruce A. ; Caillat, Thierry ; Paraskevopoulos, Konstantinos M. ; Kanatzidis, Mercouri G. / Spinodal decomposition and nucleation and growth as a means to bulk nanostructured thermoelectrics : Enhanced performance in Pb1-xSn xTe-PbS. In: Journal of the American Chemical Society. 2007 ; Vol. 129, No. 31. pp. 9780-9788.
@article{d174daa2310e481aaa3415a25df59af9,
title = "Spinodal decomposition and nucleation and growth as a means to bulk nanostructured thermoelectrics: Enhanced performance in Pb1-xSn xTe-PbS",
abstract = "The solid-state transformation phenomena of spinodal decomposition and nucleation and growth are presented as tools to create nanostructured thermoelectric materials with very low thermal conductivity and greatly enhanced figure of merit. The systems (PbTe)1-x(PbS)x and (Pb 0.95Sn0.05Te)1-x(PbS)x are not solid solutions but phase separate into PbTe-rich and PbS-rich regions to produce coherent nanoscale heterogeneities that severely depress the lattice thermal conductivity. For x gt; ∼0.03 the materials are ordered on three submicrometer length scales. Transmission electron microscopy reveals both spinodal decomposition and nucleation and growth phenomena the relative magnitude of which varies with x. We show that the (Pb0.95Sn 0.05Te)1-x(PbS)x system, despite its nanostructured nature, maintains a high electron mobility (> 100 cm 2/V·s at 700 K). At x ∼ 0.08 the material achieves a very low room-temperature lattice thermal conductivity of ∼0.4 W/m·K. This value is only 28{\%} of the PbTe lattice thermal conductivity at room temperature. The inhibition of heat flow in this system is caused by nanostructure-induced acoustic impedance mismatch between the PbTe-rich and PbS-rich regions. As a result the thermoelectric properties of (Pb0.95Sn0.05Te) 1-x(PbS)x at x = 0.04, 0.08, and 0.16 were found to be superior to those of PbTe by almost a factor of 2. The relative importance of the two observed modes of nanostructuring, spinodal decomposition and nucleation and growth, in suppressing the thermal conductivity was assessed in this work, and we can conclude that the latter mode seems more effective in doing so. The promise of such a system for high efficiency is highlighted by a ZT ∼ 1.50 at 642 K for x ∼ 0.08.",
author = "John Androulakis and Lin, {Chia Her} and Kong, {Hun Jin} and Ctirad Uher and Wu, {Chun I.} and Timothy Hogan and Cook, {Bruce A.} and Thierry Caillat and Paraskevopoulos, {Konstantinos M.} and Kanatzidis, {Mercouri G}",
year = "2007",
month = "8",
day = "8",
doi = "10.1021/ja071875h",
language = "English",
volume = "129",
pages = "9780--9788",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "31",

}

TY - JOUR

T1 - Spinodal decomposition and nucleation and growth as a means to bulk nanostructured thermoelectrics

T2 - Enhanced performance in Pb1-xSn xTe-PbS

AU - Androulakis, John

AU - Lin, Chia Her

AU - Kong, Hun Jin

AU - Uher, Ctirad

AU - Wu, Chun I.

AU - Hogan, Timothy

AU - Cook, Bruce A.

AU - Caillat, Thierry

AU - Paraskevopoulos, Konstantinos M.

AU - Kanatzidis, Mercouri G

PY - 2007/8/8

Y1 - 2007/8/8

N2 - The solid-state transformation phenomena of spinodal decomposition and nucleation and growth are presented as tools to create nanostructured thermoelectric materials with very low thermal conductivity and greatly enhanced figure of merit. The systems (PbTe)1-x(PbS)x and (Pb 0.95Sn0.05Te)1-x(PbS)x are not solid solutions but phase separate into PbTe-rich and PbS-rich regions to produce coherent nanoscale heterogeneities that severely depress the lattice thermal conductivity. For x gt; ∼0.03 the materials are ordered on three submicrometer length scales. Transmission electron microscopy reveals both spinodal decomposition and nucleation and growth phenomena the relative magnitude of which varies with x. We show that the (Pb0.95Sn 0.05Te)1-x(PbS)x system, despite its nanostructured nature, maintains a high electron mobility (> 100 cm 2/V·s at 700 K). At x ∼ 0.08 the material achieves a very low room-temperature lattice thermal conductivity of ∼0.4 W/m·K. This value is only 28% of the PbTe lattice thermal conductivity at room temperature. The inhibition of heat flow in this system is caused by nanostructure-induced acoustic impedance mismatch between the PbTe-rich and PbS-rich regions. As a result the thermoelectric properties of (Pb0.95Sn0.05Te) 1-x(PbS)x at x = 0.04, 0.08, and 0.16 were found to be superior to those of PbTe by almost a factor of 2. The relative importance of the two observed modes of nanostructuring, spinodal decomposition and nucleation and growth, in suppressing the thermal conductivity was assessed in this work, and we can conclude that the latter mode seems more effective in doing so. The promise of such a system for high efficiency is highlighted by a ZT ∼ 1.50 at 642 K for x ∼ 0.08.

AB - The solid-state transformation phenomena of spinodal decomposition and nucleation and growth are presented as tools to create nanostructured thermoelectric materials with very low thermal conductivity and greatly enhanced figure of merit. The systems (PbTe)1-x(PbS)x and (Pb 0.95Sn0.05Te)1-x(PbS)x are not solid solutions but phase separate into PbTe-rich and PbS-rich regions to produce coherent nanoscale heterogeneities that severely depress the lattice thermal conductivity. For x gt; ∼0.03 the materials are ordered on three submicrometer length scales. Transmission electron microscopy reveals both spinodal decomposition and nucleation and growth phenomena the relative magnitude of which varies with x. We show that the (Pb0.95Sn 0.05Te)1-x(PbS)x system, despite its nanostructured nature, maintains a high electron mobility (> 100 cm 2/V·s at 700 K). At x ∼ 0.08 the material achieves a very low room-temperature lattice thermal conductivity of ∼0.4 W/m·K. This value is only 28% of the PbTe lattice thermal conductivity at room temperature. The inhibition of heat flow in this system is caused by nanostructure-induced acoustic impedance mismatch between the PbTe-rich and PbS-rich regions. As a result the thermoelectric properties of (Pb0.95Sn0.05Te) 1-x(PbS)x at x = 0.04, 0.08, and 0.16 were found to be superior to those of PbTe by almost a factor of 2. The relative importance of the two observed modes of nanostructuring, spinodal decomposition and nucleation and growth, in suppressing the thermal conductivity was assessed in this work, and we can conclude that the latter mode seems more effective in doing so. The promise of such a system for high efficiency is highlighted by a ZT ∼ 1.50 at 642 K for x ∼ 0.08.

UR - http://www.scopus.com/inward/record.url?scp=34547763397&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34547763397&partnerID=8YFLogxK

U2 - 10.1021/ja071875h

DO - 10.1021/ja071875h

M3 - Article

C2 - 17629270

AN - SCOPUS:34547763397

VL - 129

SP - 9780

EP - 9788

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

SN - 0002-7863

IS - 31

ER -