高貴金属ナノクラスターにアンフィフィリシティを導入し,相移転駆動型イオンペアリング反応を通じます
Qiaofeng Yao1, Xun Yuan, Yong Yu
1Department of Chemical and Biomolecular Engineering, National University of Singapore , 10 Kent Ridge Crescent, Singapore 119260.
Journal of the American Chemical Society
|January 14, 2015
まとめ
高貴金属ナノクラスター (NCs) は,水性リガンドに水害性カチオンを結合することにより,アンフィフィリックになるように修正されました. このアンフィフィリシティは,NCが分子表面活性剤のように自己組織化することを可能にします.
科学分野:
- 表面化学について
- ナノ材料科学 ナノ材料科学
- コロイド科学 コロイド科学
背景:
- 表面活性物質の重要な特性であるアンフィフィリティは,貴金属ナノクラスター (NCs) で広く研究されていません.
- 高貴金属NC,特にサブ2nmクラスターは,ユニークな電子および光学特性を提供しているが,しばしば多用途な表面機能が欠けている.
研究 の 目的:
- 表面改変によって貴金属ナノクラスター (NCs) にアンフィフィリシティを与える.
- これらの新たに合成されたアンフィフィリックNCの自己組み立て行動とインターフェース特性を調査する.
主な方法:
- リンパ性金ナノクラスター (Au25(MHA) 18@xCTA NCs) の合成は,相移転駆動イオンペアリングによるものです.
- 改変には,Au25 NCsに水性性セチルトリメチルアモニウム (CTA+) カチオンで,水性性6メルカプトヘキサノ酸 (MHA) リガンドをパッチする.
- リガンドカバーの特徴と,様々な溶媒における溶解性の評価.
主要な成果:
- 水性MHAと水性MHA···CTAリガンドのバランスの取れた比率を持つアンフィフィリックAu25(MHA) 18@xCTANCs (x=6-9) を成功裏に作成しました.
- これらのアンフィフィリックNCは,様々な溶媒に溶解性を示し,分子アンフィフィールに似た自己組み立て行動を示した.
- アンフィフィリックNCは,空気-液体界面で堆積された二重層に自己組織化し,リオトロピック液体結晶相を模倣した.
結論:
- 表面パッチング戦略は,貴金属NCにアンフィフィリティを効果的に導入しました.
- アンフィフィリックNCは,溶解性が向上し,分子アンフィフィルのような自己組み立てが示され,潜在的な応用が拡大されています.
- この研究は,インターフェイス活動と自己組織化を必要とする領域で貴金属NCを活用するための新しい道を開きます.
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