逆水素化によるグラフェンの性質の制御:グラファンの証拠
D C Elias1, R R Nair, T M G Mohiuddin
1School of Physics and Astronomy, University of Manchester, M13 9PL, Manchester, UK.
Science (New York, N.Y.)
|January 31, 2009
まとめ
グラフィートの単一の原子層であるグラフェンは,水素と反応すると,絶縁体 (グラフェン) に変形することができます. この可逆的なプロセスは,調整可能な電子特性を可能にし,新しい2D素材を作成します.
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:
- グラファイトは化学的惰性で知られている.
- グラフィートの単一の原子平面であるグラフェンは,半金属としてユニークな電子特性を持っています.
研究 の 目的:
- 原子水素とグラフェンの化学反応性を調査するために.
- グラフェンの構造的および電子的性質の変化を調査する.
- グラフェンの潜在力を,新しい2D素材の作成のための支架として実証する.
主な方法:
- グラフェンの原子水素との反応.
- 伝送電子顕微鏡 (TEM) を用いた特徴化.
- 反応を逆転させるため,アンニングを行います.
主要な成果:
- グラフェンは原子水素と反応し,グラファンを形成し,六角格子を維持する結晶派生物ですが,より短い周期があります.
- 変換の結果,半金属から絶縁体への変化が生じます.
- 水素化プロセスは可逆であり,グラフェンの元の電子状態と,解熱時の格子間隔を復元します.
結論:
- グラフェンは,新しい二次元の材料を設計するための多用途の原子スケール・スキャフォルドとして機能します.
- グラフェンの化学的改変により,導電器を断熱器に変換するなど,調節可能な電子特性を得ることができます.
- 反応の可逆性は,グラフェン誘導体の強度と潜在的な応用を強調しています.
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