:Ge, a promising n-type thermoelectric oxide composite

详细信息    查看全文

• 作者：David Bé ; rardan ; Emmanuel Guilmeau ; Antoine Maignan ; Bernard Raveau
• 关键词：A. Indium oxide ; D. Thermopower ; D. Electrical conductivity ; D. Thermal conductivity
• 刊名：Solid State Communications
• 出版年：2008
• 出版时间：April 2008
• 年：2008
• 卷：146
• 期：1-2
• 页码：97-101
• 全文大小：904 K

文摘

We have studied the chemical, structural and transport properties of a series of In₂O₃ based samples with germanium doping (from 0 to 15 atom % ). X-ray diffraction and scanning electron microscopy studies show that the solubility limit of Ge in In₂O₃ is very small and that additions of more than about 0.5 atom % Ge lead to the presence of In₂Ge₂O₇ inclusions. The electrical conductivity is strongly enhanced by Ge doping with best values exceeding 1200 S cm⁻¹ at room temperature. On the other hand, the thermopower decreases with Ge addition, but the thermoelectric power factor remains higher than that of undoped In₂O₃ and is close to 1 mW m⁻¹ K⁻² at 1100 K in In_1.985Ge_0.015O₃. The thermal conductivity is strongly reduced by Ge additions. The dimensionless figure of merit ZT reaches 0.1 at 1273 K in In₂O₃ and exceeds 0.45 at 1273 K in composite compounds with nominal composition In_1.8Ge_0.2O₃.