Enhanced thermoelectric figure of merit in nanostructured n-type silicon germanium bulk alloy

被引：574

作者：

Wang, X. W. ^{[2
]}

Lee, H. ^{[1
]}

Lan, Y. C. ^{[2
]}

Zhu, G. H. ^{[2
,3
]}

Joshi, G. ^{[2
]}

Wang, D. Z. ^{[2
]}

Yang, J. ^{[2
]}

Muto, A. J. ^{[1
]}

Tang, M. Y. ^{[4
]}

Klatsky, J. ^{[2
]}

Song, S. ^{[2
]}

Dresselhaus, M. S. ^{[4
,5
]}

Chen, G. ^{[1
]}

Ren, Z. F. ^{[2
]}

机构：

[1] MIT, Dept Mech Engn, Cambridge, MA 02139 USA

[2] Boston Coll, Dept Phys, Chestnut Hill, MA 02467 USA

[3] GMZ Energy Inc, Newton, MA 02458 USA

[4] MIT, Dept Elect Engn & Comp Sci, Cambridge, MA 02139 USA

[5] MIT, Dept Phys, Cambridge, MA 02139 USA

来源：

APPLIED PHYSICS LETTERS | 2008年 / 93卷 / 19期

基金：

美国国家科学基金会;

关键词：

Ge-Si alloys; grain boundaries; hot pressing; nanoparticles; nanotechnology; phonons; semiconductor growth; semiconductor materials; thermal conductivity; thermoelectricity;

D O I：

10.1063/1.3027060

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The dimensionless thermoelectric figure of merit (ZT) of the n-type silicon germanium (SiGe) bulk alloy at high temperature has remained at about one for a few decades. Here we report that by using a nanostructure approach, a peak ZT of about 1.3 at 900 degrees C in an n-type nanostructured SiGe bulk alloy has been achieved. The enhancement of ZT comes mainly from a significant reduction in the thermal conductivity caused by the enhanced phonon scattering off the increased density of nanograin boundaries. The enhanced ZT will make such materials attractive in many applications such as solar, thermal, and waste heat conversion into electricity.

引用

页数：3

共 22 条

[1] SILICON-GERMANIUM ALLOYS AS HIGH-TEMPERATURE THERMOELECTRIC-MATERIALS [J].