固体構造イソマーの合成と熱特性:SnSeとMoSe2のオーダーされた相互成長
Noel S Gunning1, Joseph Feser2, Matt Beekman3
1†Department of Chemistry and Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States.
Journal of the American Chemical Society
|June 19, 2015
まとめ
研究者らは,調節された元素反応剤法を使用して,亜鉛セレニド (SnSe) とモリブデン・デセレニド (MoSe2) の新しい層の異体化合物を合成した. これらの新しい材料は,無秩序なインターフェースのために非常に低い熱伝導性を示し,熱電気アプリケーションの可能性を示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- ナノテクノロジー ナノテクノロジー
背景:
- SnSeやMoSe2のような層状の材料は,熱電学的アプリケーションに興味があります.
- 層のヘテロ構造の構造とインタフェースを制御することは,その性質を調節するために極めて重要です.
- 複雑な層状化合物の熱輸送機構を理解することは,材料設計に不可欠です.
研究 の 目的:
- (SnSe) 1.05と (MoSe2) n.n.を基にした構造同位体の一族を合成し,特徴づけること.
- 層の配列と厚さの影響がこれらの同体体の構造的および熱的性質に及ぼす影響を調査する.
- 横平面の熱伝導性を決定し,熱抵抗に寄与する要因を特定する.
主な方法:
- 調節された元素反応剤法を使用して6つの異なる同位体合成.
- X線微分と電子顕微鏡による構造特性の特徴化.
- 横平面の熱伝導性の測定. 横平面の熱伝導性の測定. 横平面の熱伝導性の測定.
主要な成果:
- 6つのユニークな構造イソマーの製造に成功し,層の配置は異なっていますが,格子パラメータは似ています.
- 合成されたすべての同位体において,非常に低い横平面熱伝導率 (∼0.08 Wm(-1) K(-1)) を観測した.
- 低熱伝送の主な原因として,ターボストラティックに乱れたヴァン・デル・ワールス界面 (SnSe-MoSe2とMoSe2-MoSe2) の特定.
結論:
- アイソメアの構成層の構造,順序,厚さは,前体配列によって決定される.
- 低熱伝導性は,インターフェースの散乱に起因し,乱雑なインターフェースが支配的な役割を果たしている.
- この発見は,構造的複雑性,インターフェース特性,層状の材料における熱伝送の関係に関する洞察を提供します.
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