表面誘発アルケンのオリゴメリゼーション:熱水溶融は本当に単層で保護されたシリコンナノ結晶につながるのでしょうか?
Zhenyu Yang1, Muhammad Iqbal, Alexander R Dobbie
1Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada.
Journal of the American Chemical Society
|October 30, 2013
まとめ
ドデセンを用いたシリコンナノ結晶 (SiNC) の表面機能化は酸素の影響を受けます. 酸素はリガンドオリゴメリゼーションを加速しますが,惰性条件と低温ではSiNCsのよりよい単層カバーが得られます.
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
- 表面化学について
背景:
- シリコンナノ結晶 (SiNCs) は,ナノテクノロジーにおいて極めて重要です.
- SiNCの表面機能化は,そのアプリケーションの鍵です.
- ハイドリド末端のSiNCは,通常,水溶塩化による機能化が行われます.
研究 の 目的:
- 熱水シル化によるドデセンのSiNCの表面機能化を再検討する.
- 反応大気と温度が水酸化とリガンドオリゴメリゼーションに与える影響を調査する.
- リガンドオリゴメリゼーションを阻害し,最適なSiNC表面覆いを達成するための方法を提案する.
主な方法:
- ハイドリド末端SiNCをドデセンで熱水塩化処理する.
- アルゴンと空気の大気下での反応の比較研究.
- 様々な温度 (100~190°C) の反応製品の分析.
主要な成果:
- アルゴンで形成されたドデシルオリゴーマー (n ≤ 4)
- 空気中に観察されたドデシルオリゴメリゼーションの増加 (n ≤ 7).
- 酸素は水酸化を加速し,シリル基形成経由でリガンドオリゴメリゼーションを促進します.
結論:
- 酸素の存在は,SiNC表面機能化中にリガンドオリゴメリゼーションを大幅に強化します.
- オリゴメリゼーションを抑制するために,低温,惰性大気,および稀なリガンド濃度が提案されています.
- 最適化された条件では,SiNCの表面に単層のカバーをもたらすことができます.
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