High-Temperature Transport Properties of the Zintl Phases Yb_(11)GaSb_9 and Yb_(11)InSb_9
Abstract
Two rare-earth Zintl phases, Yb_(11)GaSb_9 and Yb_(11)InSb_9, were synthesized in high-temperature self-fluxes of molten Ga and In, respectively. Structures were characterized by both single-crystal X-ray diffraction and powder X-ray diffraction and are consistent with the published orthorhombic structure, with the space group Iba2. High-temperature differential scanning calorimetry (DSC) and thermal gravimetry (TG) measurements reveal thermal stability to 1300 K. Seebeck coefficient and resistivity measurements to 1000 K are consistent with the hypothesis that Yb_(11)GaSb_9 and Yb_(11)InSb_9 are small band gap semiconductors or semimetals. Low doping levels lead to bipolar conduction at high temperature, preventing a detailed analysis of the transport properties. Thermal diffusivity measurements yield particularly low lattice thermal conductivity values, less than 0.6 W/m K for both compounds. The low lattice thermal conductivity suggests that Yb_(11)MSb_9 (M = Ga, In) has the potential for high thermoelectric efficiency at high temperature if charge-carrier doping can be controlled.
Additional Information
© 2010 American Chemical Society. Received June 26, 2009. Revised Manuscript Received October 29, 2009. Publication Date (Web): November 23, 2009. We gratefully acknowledge the financial support from NSF DMR0600742, the NASA Jet Propulsion Laboratory, and the Beckman Foundation. A pdf showing the microprobe image and elemental mapping of the hot pressed pellets is provided. This material is available free of charge via the Internet at http://pubs.acs.org.Attached Files
Supplemental Material - cm901824c_si_001.pdf
Files
Name | Size | Download all |
---|---|---|
md5:226cf846844c392d64b88e89d4219776
|
2.3 MB | Preview Download |
Additional details
- Eprint ID
- 17580
- Resolver ID
- CaltechAUTHORS:20100224-112243080
- DMR0600742
- NSF
- NASA/JPL
- Beckman Foundation
- Created
-
2010-02-24Created from EPrint's datestamp field
- Updated
-
2021-11-08Created from EPrint's last_modified field