Traversing the Metal-Insulator Transition in a Zintl Phase: Rational Enhancement of Thermoelectric Efficiency in Yb14Mn1-xAlxSb11

被引：289

作者：

Toberer, Eric S. ^{[1
]}

Cox, Catherine A. ^{[2
]}

Brown, Shawna R. ^{[2
]}

Ikeda, Teruyuki ^{[1
]}

May, Andrew F. ^{[1
]}

Kauzlarich, Susan M. ^{[2
]}

Snyder, G. Jeffrey ^{[1
]}

机构：

[1] CALTECH, Pasadena, CA 91125 USA

[2] Univ Calif Davis, Dept Chem, Davis, CA 95616 USA

来源：

ADVANCED FUNCTIONAL MATERIALS | 2008年 / 18卷 / 18期

关键词：

D O I：

10.1002/adfm.200800298

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

For high temperature thermoelectric applications, Yb14MnSb11 has a maximum thermoelectric figure of merit (zT) of similar to 1.0 at a high zT is found despite a carrier concentration that is higher than typical thermoelectric materials. Here, we reduce the carrier concentration with the discovery of a continuous transition between metallic Yb14MnSb11 and semiconducting Yb(1)4AlSb(11). Yb14Mn1-xAlxSb11 forms a solid solution where the free carrier concentration gradually changes as expected from the Zintl valence formalism. Throughout this transition the electronic properties are found to obey a rigid band model with a band gap of 0.5 eV and an effective mass of 3 m(c). As the carrier concentration decreases, an increase in the Seebeck coefficient is observed at the expense of an increased electrical resistivity. At the optimum carrier concentration. a maximum zT of 1.3 at 1223 K is obtained, which is more than twice that of the state-of-the-art Si0.8Ge0.2 flown by NASA.

引用

页码：2795 / 2800

页数：6

共 22 条

[1] Improved thermoelectric performance in Yb14Mn1-xZnxSb11 by the reduction of spin-disorder scattering [J].