炭素ナノチューブの電子特性の極度の酸素感受性
1Department of Physics, University of California at Berkeley, and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|March 10, 2000
まとめ
単一壁の炭素ナノチューブは,その化学的環境に対して極端に敏感である. 吸収されたガスは,その電子特性を逆転的に変化させ,センサーとしての使用に影響を与え,潜在的に固有の測定を損なう可能性があります.
科学分野:
- マテリアルサイエンス 材料科学
- ナノテクノロジー ナノテクノロジー
- 凝縮物質物理学 凝縮物質物理学
背景:
- シングルウォールカーボンナノチューブ (SWCNT) は,ユニークな電子特性を有しています.
- SWCNTに対する環境の影響を理解することは,その適用にとって極めて重要です.
研究 の 目的:
- 化学環境がSWCNTの電子特性に与える影響を調査する.
- 吸収されたガスに対するSWCNTの感受性を調査する.
主な方法:
- 輸送測定 輸送測定
- スキャニング・トンネリング・スペクトロスコピー
主要な成果:
- SWCNTの電子特性 (抵抗,熱電源,状態の局所密度) は,空気/酸素への曝露に対して非常に敏感である.
- 吸収されたガスの少量の濃度は,これらの電子パラメータを可逆的に調節することができます.
- 半導体SWCNTは,ガス曝露時に金属的行動を示すことができる.
結論:
- SWCNTは,繊細な化学ガスセンサーとしての可能性を示しています.
- 外部的な空気への曝露の影響は,準備されたSWCNTの測定された性質を大幅に変化させることができ,慎重に検討する必要があります.
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