Abstract
Previous efforts to enhance thermoelectric performance have primarily focused on reduction in lattice thermal conductivity caused by broad-based phonon scattering across multiple length scales. Herein, we demonstrate a design strategy which provides for simultaneous improvement of electrical and thermal properties of p-type PbSe and leads to ZT ∼ 1.6 at 923 K, the highest ever reported for a tellurium-free chalcogenide. Our strategy goes beyond the recent ideas of reducing thermal conductivity by adding two key new theory-guided concepts in engineering, both electronic structure and band alignment across nanostructure-matrix interface. Utilizing density functional theory for calculations of valence band energy levels of nanoscale precipitates of CdS, CdSe, ZnS, and ZnSe, we infer favorable valence band alignments between PbSe and compositionally alloyed nanostructures of CdS1-xSe x/ZnS1-xSex. Then by alloying Cd on the cation sublattice of PbSe, we tailor the electronic structure of its two valence bands (light hole L and heavy hole Σ) to move closer in energy, thereby enabling the enhancement of the Seebeck coefficients and the power factor.
| Original language | English |
|---|---|
| Pages (from-to) | 7364-7370 |
| Number of pages | 7 |
| Journal | Journal of the American Chemical Society |
| Volume | 135 |
| Issue number | 19 |
| DOIs | |
| Publication status | Published - May 15 2013 |
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ASJC Scopus subject areas
- Chemistry(all)
- Catalysis
- Biochemistry
- Colloid and Surface Chemistry
Cite this
High thermoelectric performance via hierarchical compositionally alloyed nanostructures. / Zhao, Li Dong; Hao, Shiqiang; Lo, Shih Han; Wu, Chun I.; Zhou, Xiaoyuan; Lee, Yeseul; Li, Hao; Biswas, Kanishka; Hogan, Timothy P.; Uher, Ctirad; Wolverton, C.; Dravid, Vinayak P.; Kanatzidis, Mercouri G.
In: Journal of the American Chemical Society, Vol. 135, No. 19, 15.05.2013, p. 7364-7370.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - High thermoelectric performance via hierarchical compositionally alloyed nanostructures
AU - Zhao, Li Dong
AU - Hao, Shiqiang
AU - Lo, Shih Han
AU - Wu, Chun I.
AU - Zhou, Xiaoyuan
AU - Lee, Yeseul
AU - Li, Hao
AU - Biswas, Kanishka
AU - Hogan, Timothy P.
AU - Uher, Ctirad
AU - Wolverton, C.
AU - Dravid, Vinayak P.
AU - Kanatzidis, Mercouri G
PY - 2013/5/15
Y1 - 2013/5/15
N2 - Previous efforts to enhance thermoelectric performance have primarily focused on reduction in lattice thermal conductivity caused by broad-based phonon scattering across multiple length scales. Herein, we demonstrate a design strategy which provides for simultaneous improvement of electrical and thermal properties of p-type PbSe and leads to ZT ∼ 1.6 at 923 K, the highest ever reported for a tellurium-free chalcogenide. Our strategy goes beyond the recent ideas of reducing thermal conductivity by adding two key new theory-guided concepts in engineering, both electronic structure and band alignment across nanostructure-matrix interface. Utilizing density functional theory for calculations of valence band energy levels of nanoscale precipitates of CdS, CdSe, ZnS, and ZnSe, we infer favorable valence band alignments between PbSe and compositionally alloyed nanostructures of CdS1-xSe x/ZnS1-xSex. Then by alloying Cd on the cation sublattice of PbSe, we tailor the electronic structure of its two valence bands (light hole L and heavy hole Σ) to move closer in energy, thereby enabling the enhancement of the Seebeck coefficients and the power factor.
AB - Previous efforts to enhance thermoelectric performance have primarily focused on reduction in lattice thermal conductivity caused by broad-based phonon scattering across multiple length scales. Herein, we demonstrate a design strategy which provides for simultaneous improvement of electrical and thermal properties of p-type PbSe and leads to ZT ∼ 1.6 at 923 K, the highest ever reported for a tellurium-free chalcogenide. Our strategy goes beyond the recent ideas of reducing thermal conductivity by adding two key new theory-guided concepts in engineering, both electronic structure and band alignment across nanostructure-matrix interface. Utilizing density functional theory for calculations of valence band energy levels of nanoscale precipitates of CdS, CdSe, ZnS, and ZnSe, we infer favorable valence band alignments between PbSe and compositionally alloyed nanostructures of CdS1-xSe x/ZnS1-xSex. Then by alloying Cd on the cation sublattice of PbSe, we tailor the electronic structure of its two valence bands (light hole L and heavy hole Σ) to move closer in energy, thereby enabling the enhancement of the Seebeck coefficients and the power factor.
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U2 - 10.1021/ja403134b
DO - 10.1021/ja403134b
M3 - Article
VL - 135
SP - 7364
EP - 7370
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 19
ER -