Effects of P doping on the thermoelectric properties of β-FeSi2

被引：43

作者：

Ito, M ^{[1
]}

Nagai, H ^{[1
]}

Oda, E ^{[1
]}

Katsuyama, S ^{[1
]}

Majima, K ^{[1
]}

机构：

[1] Osaka Univ, Grad Sch Engn, Dept Mat Sci & Proc, Suita, Osaka 5650871, Japan

来源：

JOURNAL OF APPLIED PHYSICS | 2002年 / 91卷 / 04期

关键词：

D O I：

10.1063/1.1436302

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The effects of P substitution for Si as an n-type dopant on the thermoelectric properties of hot-pressed beta-FeSi2 were investigated. The Seebeck coefficient, electrical resistivity, and thermal conductivity of the FeSi2-xPx were measured from room temperature to 1100 K, and then the power factor and figure of merit were evaluated. The Seebeck coefficient of the hot-pressed FeSi2-xPx was negative, indicating that P atoms were definitely substituted for Si atoms as an n-type dopant in the beta phase. The samples with x=0.02 and 0.04 had a Seebeck coefficient greater than that of the conventional hot-pressed Fe0.98Co0.02Si2 below 800 K. The electrical resistivity was significantly reduced by P doping, especially in the lower temperature range, and slightly decreased with increasing P content. The log rho-1/T plots of the P-doped samples exhibited a specific behavior below 480 K, which was not observed in the case of the nondoped sample. The thermal conductivity of the P-doped sample was smaller than that of the nondoped sample in spite of the larger amount of the metallic epsilon phase. The figure of merit was significantly enhanced by P doping as compared with that of the nondoped beta-FeSi2, and a high thermoelectric performance, almost the same as that of the conventional Fe0.98Co0.02Si2, was obtained by P doping into beta-FeSi2. (C) 2002 American Institute of Physics.

引用

页码：2138 / 2142

页数：5