超低熱伝導性と優れた熱電性を持つ複合結晶構造の新材料: Tl2Ag12Te7+δ
Yixuan Shi1, Abdeljalil Assoud1, Simeon Ponou2
1Department of Chemistry and Waterloo Institute for Nanotechnology , University of Waterloo , Waterloo , Ontario , Canada N2L 3G1.
Journal of the American Chemical Society
|June 19, 2018
まとめ
新しい熱電気材料であるTl2Ag12Te7+δは,超低熱伝導性と高い性能を示し,エネルギー用途に有望である.
科学分野:
- 材料科学
- 固体化学
- 凝縮物質物理学
背景:
- 熱電気材料は熱を電気に変換し,その逆も行います.
- エネルギー利用には,高効率と低熱伝導性を有する材料の開発が不可欠です.
- 既存の熱電性材料は,高温での性能または安定性においてしばしば制限に直面します.
研究 の 目的:
- 新しい熱電性物質Tl2Ag12Te7+δを合成し特徴づけること.
- この新しい化合物の 構造的,電子的,熱電気的性質を調査する
- 熱電気エネルギーの効率的な変換の可能性を評価する.
主な方法:
- 従来の固体反応合成です
- 結晶構造の決定のためのX線 difraktion (超空間グループ精細化).
- WIEN2k パッケージを使用した電子構造計算.
- 物理的性質の測定 (熱伝導性,熱電性)
主要な成果:
- 新しい熱電性物質Tl2Ag12Te7+δが成功して合成されました.
- この材料は ~0.25 W m−1 K−1 の超低熱伝導性を示しています.
- 525Kでは高値 (ZT) が1.1まで達成された.
- 結晶構造はTl2Ag12Te6フレームと線形Te鎖の複合体である.
- 電子構造の計算は,Te含有量に応じて半導体または金属の振る舞いを示し,測定は半導体特性を確認した.
結論:
- Tl2Ag12Te7+δは最先端の熱電性材料として有望です
- そのユニークな複合構造と超低熱伝導性は,高温下での優れた熱電気性能に貢献します.
- この発見は 廃棄熱の回収と発電のための 効率的な熱電気材料の設計に 新たな道を開きます
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