Sn空白を抑制することによって,競争力のあるN型SnTe熱電器の実現
Huimei Pang1, Yuting Qiu2, Dongyang Wang1
1School of Materials Science and Engineering, Beihang University, Beijing 100191, China.
Journal of the American Chemical Society
|June 2, 2021
まとめ
タン・テルリド (SnTe) 熱電材料の開発は,タン空白のために困難です. この研究では,鉛合金による空白の減少とヨウ素ドーピングによる電子の添加により,高性能のn型SnTeを成功裏に合成した.
科学分野:
- 材料科学
- 固体物理学
- ナノテクノロジー
背景:
- タンテルリド (SnTe) は有望な熱電気材料ですが,固有のタン空白のためにn型伝導性を達成することは困難です.
- 効率的なn型SnTeの開発は,n型とp型両脚に基づく費用対効果の高い熱電気装置の実現に不可欠です.
研究 の 目的:
- 高性能なn型SnTe熱電気材料を合成する.
- 電子ドーピングを導入する.
- 熱電特性に対する合金とドーピングの影響を調査する.
主な方法:
- 鉛 (Pb) の合金で合成されたn型SnTeは,スチーン (Sn) の空白を抑制する.
- 電子ドーピングを導入し,ヨウ素 (I) を使用して電流をp型からn型にシフトさせる.
- 送信電子顕微鏡を用いて空白を確認した.
主要な成果:
- Pbの合金化により,Snの空白が効果的に満たされ,その濃度が低下する.
- ヨウ素のドーピングにより 物質はn型導電性を 獲得しました
- 鋭い伝導帯 (Pb合金) を通じて電気伝導性が向上し,フォノン散布 (Pb合金とIドーピング) を通して格子熱伝導性が低下した.
- n型Sn0.6Pb0.4Te0.98I0.02に対して573 Kで最大値 (ZTmax) を約0.8と,平均ZTaveを約0.51と達成した.
結論:
- 高性能なn型SnTe熱電気材料を成功裏に開発した.
- Snの空白を抑制し,その後の電子ドーピングの戦略は有効です.
- 達成された性能は,p型SnTeと非常に一致し,n型SnTeを熱電発電の有効な候補にしています.
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