水素のないCVDにおけるサブナノメートルの直径の単面カーボンナノチューブ配列の選択的成長
Lixing Kang1,2,3, Shibin Deng1, Shuchen Zhang1
1Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, P. R. China.
Journal of the American Chemical Society
|September 23, 2016
まとめ
研究者らは,固体モリブデン炭化物触媒を使用して,制御されたキラリティを持つ小径単面カーボンナノチューブ (SWNT) 配列を育成する方法を開発した. この進歩は,高性能の近赤外線光電子機器にとって極めて重要です.
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:
- 単一壁の炭素ナノチューブ (SWNT) は,先進的な光電子装置にとって極めて重要です.
- SWNTの直径とキラリティを制御することは,その光学的および電子的特性を最適化するための鍵です.
- 帯域間隔が大きいサブナノメートル直径のSWNTは,特に近赤外線アプリケーションに望ましい.
研究 の 目的:
- 適正な直径のサブナノメートルのSWNT配列の選択的な成長方法を開発する.
- 成長したSWNTで狭いキラリティの分布を達成するために.
- SWNTの密度を高めて 装置を製造する
主な方法:
- 固体モリブデン炭化物 (Mo2C) 触媒を用いてSWNTの成長.
- 低炭素の栄養と,水素のない化学蒸気堆積 (CVD) 環境での短い成長時間を使用します.
- SWNTの特性に対する触媒のサイズとアニリングプロセスの役割を調査する.
- SWNTの直径,密度,キラリティの分布を特徴づけている.
主要な成果:
- サブナノメートルの直径 (0.75~0.95 nm) の配列SWNTを成功裏に成長させました.
- 狭いキラリティ分布が達成され,特定のキラリティが優勢 (> 73%) であった.
- 触媒のサイズと炭素の供給速度を操作することによってSWNTの成長を制御することが示されています.
- サファイア基板のSWNT密度は,アニリングによって15チューブ/μmに増加した.
結論:
- 固体Mo2C触媒は,制御されたキラリティのサブナノメートルSWNTの選択的,短時間の成長を可能にします.
- この方法は,SWNTの特性を特定のアプリケーションに合わせるための経路を提供します.
- この研究は,ナノエレクトロニクスにおける並べられたSWNTの構造制御のための貴重な洞察を提供します.
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