オクタ-p-フェニレンを含む自己組み立て分子樹:ナノ結晶からナノカプセルへ
Yong-Sik Yoo1, Jin-Ho Choi, Ji-Ho Song
1Center for Supramolecular Nano-Assembly and Department of Chemistry, Yonsei University, Shinchon 134, Seoul 120-749, Korea.
Journal of the American Chemical Society
|May 20, 2004
まとめ
樹状の分子は,ヘッドグループサイズに基づいて,異なるナノ構造に自己組み立てます. 小さなヘッドはラメラー構造を形成し,大きなヘッドは溶媒条件に応じて3D超結晶または空洞のナノカプセルを作成します.
科学分野:
- 超分子化学 超分子化学
- 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
背景:
- デンドリマーとデンドリート分子には,自己組織化のためのユニークな構造的特性があります.
- 分子構造の制御は,新しいナノ材料の設計の鍵です.
研究 の 目的:
- 異なる柔軟なヘッドグループを持つ木形の分子を合成し,特徴づけること.
- 溶液中のこれらの分子の自己組み立て行動を調査する.
- 異なるナノ構造物の形成とその性質を調査する.
主な方法:
- オクタ-p-フェニレンベースの木形の分子の合成.
- 構造分析のためのX線散射および伝送電子顕微鏡 (TEM).
- 電子特性を研究するための光学スペクトロスコピー.
- 動的および静的光散射,集積の特徴化のためのスキャニング電子顕微鏡 (SEM).
主要な成果:
- 小さな柔軟な頭を持つ分子が,自己組織化してラメラ構造に組み込まれている.
- より大きな頭を持つ分子は,3Dの原始的なオーソロームビック型超結晶に組織される離散のヘプタメリックスバンドルを形成しました.
- 選択性溶媒では,分子からカプセル状の空洞の集積物が形成される.
- 光学特性は,ラメラー構造と3D超結晶構造の間で異なっていた.
結論:
- 樹状の分子は,平行配列で組織されたナノ結晶を形成することができます.
- 半径配列の空洞なナノカプセルも実現可能である.
- セルフアセンブリの結果は,分子設計 (ヘッドグループサイズ) と溶媒環境によって調整可能です.
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