Synthesis of high performance thermoelectric materials by use of percolation phenomenon

2015 Fiscal Year Final Research Report

• Project/Area Number: 26630366
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Material processing/Microstructural control engineering
• Research Institution: Osaka University
• Principal Investigator: Katsuyama Shigeru 大阪大学, 工学(系)研究科(研究院), 准教授 (00224478)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 熱電変換 / 複合焼結体 / 電気伝導率 / 熱伝導率 / Ｓｉ / パーコレーション

Outline of Final Research Achievements

Si-SiO2 sintered composites were prepared by the hot-pressing from the Si powder doped with 1at.% B and the SiO2 powder. The thermal conductivity of the composite monotonously increased with an increase of the volume fraction of Si, while the electrical conductivity rapidly increased at over 40 vol.% of Si. This behavior is known as percolation phenomenon, and can be understood by the effective media approximation theory by Bruggemann. The composite with 80 vol.% Si showed the maximum dimensionless figure of merit, ZT, of 0.23 at 1073K, which was about 10% larger than that of the sintered Si doped with B.

Free Research Field

工学