通过相转移驱动的离子配对反应向贵金属纳米集群引入两性
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
概括
贵金属纳米集群 (NCs) 经过修改,通过将疏水性离子连接到疏水性联体,使其变得两性. 这种两性使NC能够像分子表面活性剂一样自我组装.
科学领域:
- 表面化学 表面化学
- 纳米材料科学 科学 纳米材料科学
- 体科学 体科学 体科学
背景情况:
- 表面活性剂的关键性质 - - 两性 - - 在贵金属纳米集群 (NCs) 中尚未得到广泛研究.
- 贵金属NCs,特别是亚2纳米集群,提供独特的电子和光学特性,但往往缺乏多用途的表面功能.
研究的目的:
- 通过表面修饰,为贵金属纳米集群 (NCs) 赋予两性.
- 研究这些新合成的两性NC的自我组装行为和接口特性.
主要方法:
- 通过相转移驱动的离子配对合成两性黄金纳米集群 (Au25(MHA) 18@xCTANCs).
- 修改涉及在Au25NCs上用性 cetyltrimethylammonium (CTA+) 离子对au25NCs进行性 6-mercaptohexanoic 酸 (MHA) 连接.
- 介质覆盖的表征和在各种溶剂中溶解度的评估.
主要成果:
- 成功创建了两性Au25(MHA) 18@xCTANCs (x=6-9),其中性MHA和性MHA···CTA连接体的比例平衡.
- 这些两性NCs在各种溶剂中表现出溶解性,并表现出类似于分子两的自我组装行为.
- 两性NCs在空气-液体接口上自组织成堆叠的双层,模仿热液体晶体相.
结论:
- 表面补丁策略有效地为贵金属NCs引入了两性.
- 两性NCs显示增强的溶解性和分子两类的自我组装,扩大其潜在的应用.
- 这项工作为在需要界面活动和自我组织的领域中利用贵金属NC开辟了新的途径.
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