一次元のヴァン・デル・ワールスの異質構造

Rong Xiang¹, Taiki Inoue², Yongjia Zheng²

¹Department of Mechanical Engineering, The University of Tokyo, Tokyo 113-8656, Japan. xiangrong@photon.t.u-tokyo.ac.jp maruyama@photon.t.u-tokyo.ac.jp.

Science (New York, N.Y.)

|February 1, 2020

まとめ

研究者らは,炭素ナノチューブ (SWCNT) に六角性ボロン窒化物 (BN) とモリブデン二酸化物 (MoS2) を共軸的に積み重ねることで,新しい材料の機能性を合成した.

科学分野:

材料科学
ナノテクノロジー
凝縮物質物理学

背景:

ヴァン・デル・ワールスのヘテロ構造は,2次元材料を積み重ねることで調整可能な性質を提供します.
1D ヴァン・デル・ワールスのヘテロ構造は,緊張と組み立ての複雑さのために合成することが難しい.

研究の目的:

1D ヴァン・デル・ワールスの異質構造を実験的に合成し,特徴づけること.
シングルウォールカーボンナノチューブ (SWCNT) の上での六角性ボロン窒化物 (BN) とモリブデン二硫化物 (MoS2) の同軸堆積を実証する.

主な方法:

単結晶のBNとMoS2層をSWCNTに同軸で積み重ねている.
ストレスの影響を軽減するために,より大きな直径のSWCNTを合成する.
合成ヘテロ構造の構造検証のための電子 difraktion.

主要な成果:

SWCNTで同軸的に積み重ねられたBNとMoS2による1Dヴァン・デル・ワールスの異質構造の成功合成.
内部のSWCNT,中部のBNナノチューブ,外部のMoS2ナノチューブを持つ5nm直径のヘテロ構造の実証.
電子 difraktionは,ヘテロ構造のすべての殻の単結晶性を確認しました.

結論:

1D ヴァン・デル・ワールスのヘテロ構造の実験的合成は可能である.
このアプローチは,既存の2D素材から,機能指定可能な多様な1Dヘテロ構造を作成することを可能にします.
1Dナノマテリアルに合わせた電子的,物理的特性を発見しました

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