Power Factor Enhancement by Modulation Doping in Bulk Nanocomposites

被引：466

作者：

Zebarjadi, Mona ^{[2
]}

Joshi, Giri ^{[1
]}

Zhu, Gaohua ^{[1
]}

Yu, Bo ^{[1
]}

Minnich, Austin ^{[2
]}

Lan, Yucheng ^{[1
]}

Wang, Xiaowei ^{[1
]}

Dresselhaus, Mildred ^{[3
,4
]}

Ren, Zhifeng ^{[1
]}

Chen, Gang ^{[2
]}

机构：

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

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

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

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

来源：

NANO LETTERS | 2011年 / 11卷 / 06期

关键词：

Electrical transport; thermoelectrics; modulation doping; nanocomposites; HIGH-THERMOELECTRIC PERFORMANCE; FIGURE-OF-MERIT; PBTE;

D O I：

10.1021/nl201206d

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

We introduce the concept of modulation doping in three-dimensional nanostructured bulk materials to increase the thermoelectric figure of merit. Modulation-doped samples are made of two types of nanograins (a two-phase composite), where dopants are incorporated only into one type. By band engineering, charge carriers could be separated from their parent grains and moved into undoped grains, which would result in enhanced mobility of the carriers in comparison to uniform doping due to a reduction of ionized impurity scattering. The electrical conductivity of the two-phase composite can exceed that of the individual components, leading to a higher power factor. We here demonstrate the concept via experiment using composites made of doped silicon nanograins and intrinsic silicon germanium grains.

引用

页码：2225 / 2230

页数：6

共 36 条

[1] Exploring Resonance Levels and Nanostructuring in the PbTe-CdTe System and Enhancement of the Thermoelectric Figure of Merit [J].