反电荷纳米粒子的离子类行为
Alexander M Kalsin1, Bartlomiej Kowalczyk, Stoyan K Smoukov
1Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, USA.
Journal of the American Chemical Society
|November 23, 2006
概括
反向带电的纳米粒子聚合并沉在电子中性. 这种纳米尺度的现象形成了通过静电选稳定的核心和外结构,类似于离子沉.
科学领域:
- 合体和表面科学科学
- 纳米技术纳米技术
- 电化学 电化学 电化学
背景情况:
- 具有不同电荷和大小的纳米粒子混合物表现出复杂的聚合行为.
- 了解纳米粒子相互作用对于材料科学和药物输送中的应用至关重要.
研究的目的:
- 为了研究负荷相反的纳米粒子混合物的沉行为.
- 阐明控制纳米粒子聚合的结构和静电机制.
主要方法:
- 制备具有受控电荷比率和大小的纳米粒子混合物.
- 使用显微镜和动态光散射观察沉动力学和聚合物结构.
主要成果:
- 沉仅发生在电子中立点,不管纳米粒子的大小或电荷比率.
- 观察到核心和外纳米粒子聚合物的形成.
- 由具有相同电荷的粒子组成的外通过有效的静电选来稳定.
结论:
- 电子中立性是反电荷纳米粒子沉的关键条件.
- 观察到的现象类似于离子溶液中的值沉.
- 核心和外聚合物的形成是由纳米级的静电相互作用和选效应驱动的.
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