2018 Fiscal Year Final Research Report
Pyrochlore lattice system as a high-performance energy conversion material
| Project/Area Number |
16H03848
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Applied materials
|
|---|
| Research Institution | Nagoya University |
|---|
Principal Investigator |
|
|---|
| Research Collaborator |
Takenaka Koshi
Yamakawa Youichi
Sawa Hiroshi
|
|---|
| Project Period (FY) |
2016-04-01 – 2019-03-31
|
| Keywords | 熱電変換材料 / パイロクロア構造 / エネルギー変換材料 |
|---|
| Outline of Final Research Achievements |
We studied thermoelectric properties of pyrochlore-lattice systems with transition metal atoms, which are expected to show high thermoelectric performance due to the geometrical frustration, multiple degrees of freedom, and rattling effects. We focused on the b-pyrochlore oxide CsW2O6 and found that this compound has large thermoelectric power as a metallic system and very small thermal conductivity probably coming from the rattling effect. We also found that Ta4SiTe4 and Nb4SiTe4, where one-dimensional chains form a triangular lattice, show excellent thermoelectric performance exceeding the practical level at low temperatures.
|
| Free Research Field |
固体化学
|
| Academic Significance and Societal Importance of the Research Achievements |
現在、熱電変換は室温付近における赤外線センサーの冷却などの限定された用途でのみ実用化されている。本研究では、CsW2O6やTa4SiTe4といった物質が、熱電変換の幅広い実用に繋がる次世代の熱電変換材料の有力候補であることを見出した。特に、Ta4SiTe4は現在熱電冷却用の材料として唯一実用化されているBi2Te3系材料が利用できないマイナス50℃以下の低温領域で高い性能を示す点でユニークである。低温領域における各種デバイスの局所冷却や、液化天然ガスの冷熱を利用した発電など、これまで実用化されていない様々な用途の実用に道を拓く成果といえる。
|
