オレフィンとミックスメチル/チエニル単層のヘックコップリングは,Si(111) 表面上のメチル/チエニル単層に結合する
Leslie E O'Leary1, Michael J Rose, Tina X Ding
1Beckman Institute and Kavli Nanosciences Institute, Division of Chemistry and Chemical Engineering, 210 Noyes Laboratory, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|June 28, 2013
まとめ
研究者はヘック反応を用いて,シリコン表面を有機分子で機能化し,表面再結合速度を大幅に低下させた. この方法により,高度なシリコン光電極の頑丈な電子結合が可能になります.
科学分野:
- 表面化学について
- マテリアルサイエンス 材料科学
- オーガニック・エレクトロニクス
背景:
- シリコン (Si) 表面は電子機器にとって極めて重要ですが,表面再結合の傾向があります.
- Si表面の機能化は,それらの電子特性を改善し,新しいアプリケーションを可能にすることができます.
研究 の 目的:
- ヘック反応を用いて小分子をSi(111) 表面に結合させる方法を開発する.
- 表面機能化が電荷移転と表面再結合速度に与える影響を調査する.
- シリコン光電極のための堅牢な結合を作り出すために.
主な方法:
- Si(111) の機能化は,メチルとチエニル単層を混合したものです.
- オレフィンと機能化されたSi表面のヘックカップリング.
- アリルハリド表面のブロミネーションとパラジウム触媒による活性化.
- さまざまな有機基質 (4-フッ素チレン,ビニルフェロセーン,プロトポルフィリンIXジメチルエステル) の結合.
主要な成果:
- 混合CH3 / SC4H3-Si ((111)) 表面は,チエニルのみの表面 (S = 670 ± 190 cm s ((-1)) と比較して,表面再結合速度が著しく低下した (S = 27 ± 9 cm s ((-1)) を示しました.
- ヴィニルフェロセンの成功した結合は,電子の容易な移転と強固な表面結合を示した.
- 最終的なヘックカップリングされた表面は,高い品質を示す低いS値 (70cm s(-1) を維持しました.
結論:
- ヘック反応は,改善された電子特性を持つ機能化されたシリコン表面を作成するための多用途な経路を提供します.
- この多段階の合成アプローチにより,小さな分子とシリコン光電極の強固な結合が可能になります.
- 開発された方法は,高性能のシリコンベースの電子および光電子機器の製造に有望である.
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