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Realization of high thermoelectric performance in n-type partially filled skutterudites

Published online by Cambridge University Press:  18 May 2011

Xun Shi ,
Shengqiang Bai ,
Lili Xi ,
Jiong Yang ,
Wenqing Zhang ,
Lidong Chen  and
Jihui Yang
Xun Shi*
Affiliation:
State Key Laboratory of High Performance Ceramics and Superfine Microstructure and CAS Key Laboratory of Energy-conversion Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
Shengqiang Bai
Affiliation:
State Key Laboratory of High Performance Ceramics and Superfine Microstructure and CAS Key Laboratory of Energy-conversion Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
Lili Xi
Affiliation:
State Key Laboratory of High Performance Ceramics and Superfine Microstructure and CAS Key Laboratory of Energy-conversion Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
Jiong Yang
Affiliation:
State Key Laboratory of High Performance Ceramics and Superfine Microstructure and CAS Key Laboratory of Energy-conversion Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
Wenqing Zhang*
Affiliation:
State Key Laboratory of High Performance Ceramics and Superfine Microstructure and CAS Key Laboratory of Energy-conversion Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
Lidong Chen
Affiliation:
State Key Laboratory of High Performance Ceramics and Superfine Microstructure and CAS Key Laboratory of Energy-conversion Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
Jihui Yang
Affiliation:
Chemical Sciences and Materials Systems Laboratory, GM R&D Center, Warren, Michigan 48090
*
a)Address all correspondence to these authors. e-mail: xshi@mail.sic.ac.cn
b)e-mail: wqzhang@mail.sic.ac.cn
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Abstract

Skutterudites are among the most exciting thermoelectric (TE) materials that could be used for various intermediate temperature applications. This study summarized our recent work on n-type partially filled skutterudites. By combining theoretical and experimental approaches, we revealed the underlying mechanism of void filling in the intrinsic lattice voids in CoSb3. With that, the electronegativity selection rule is established for the current stable filled skutterudites and further used for the discovery of a few novel filled CoSb3 compounds. The correlation between the thermal/electrical transport properties and impurity fillers in n-type partially filled skutterudites was also carefully investigated. Our results provide fundamental understanding to how those filler impurities affect electronic structures and lattice dynamics. Based on these basic understanding on transport mechanisms and sophisticated strategy in materials synthesis, TE figure of merit for n-type materials were continually increased from 1.1 to 1.4 and then to 1.7 for single-, double-, and triple-filled skutterudites.

Keywords

ThermoelectricSemiconductingEnergy generation
Type
Reviews
Information
Journal of Materials Research , Volume 26 , Issue 15: Focus Issue: Advances in Thermoelectric Materials , 14 August 2011 , pp. 1745 - 1754
Copyright
Copyright © Materials Research Society 2011

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