Abstract
Thermoelectric materials can directly generate electrical power from waste heat but the challenge is in designing efficient, stable and inexpensive systems. Nanostructuring in bulk materials dramatically reduces the thermal conductivity but simultaneously increases the charge carrier scattering, which has a detrimental effect on the carrier mobility. We have experimentally achieved concurrent phonon blocking and charge transmitting via the endotaxial placement of nanocrystals in a thermoelectric material host. Endotaxially arranged SrTe nanocrystals at concentrations as low as 2% were incorporated in a PbTe matrix doped with Na 2 Te. This effectively inhibits the heat flow in the system but does not affect the hole mobility, allowing a large power factor to be achieved. The crystallographic alignment of SrTe and PbTe lattices decouples phonon and electron transport and this allows the system to reach a thermoelectric figure of merit of 1.7 at ∼800 K.
Original language | English (US) |
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Pages (from-to) | 160-166 |
Number of pages | 7 |
Journal | Nature chemistry |
Volume | 3 |
Issue number | 2 |
DOIs | |
State | Published - Feb 2011 |
Funding
This work was supported by the Office of Naval Research (grant N00014-08-1-0613). Transmission electron microscopy work was performed in the (EPIC) (NIFTI) (Keck-II) facility of NUANCE Center at Northwestern University. NUANCE Center is supported by NSF-NSEC, NSF-MRSEC, Keck Foundation, the State of Illinois, and Northwestern University. The work at the University of Michigan is supported as part of the Revolutionary Materials for Solid State Energy Conversion, an Energy frontier Research Center funded by the U. S. Department of Energy, Office of Basic Energy Sciences under Award Number DE-SC0001054.
ASJC Scopus subject areas
- General Chemistry
- General Chemical Engineering