在水中控制合成单分散银纳米立方体
Dabin Yu1, Vivian Wing-Wah Yam
1Center for Carbon-Rich Molecular and Nano-Scale Metal-Based Materials Research and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, PR China.
Journal of the American Chemical Society
|October 14, 2004
概括
研究人员用修改的银镜反应在水中合成了单分散银纳米立方体. 这些精确定义的纳米立方体形成稳定的解决方案,并组装成二维数组.
科学领域:
- 纳米技术 纳米技术
- 材料科学 材料科学 材料科学
- 化学 化学 化学
背景情况:
- 银纳米晶在各种应用中至关重要.
- 控制纳米晶体的大小,形状和组装是定制性质的关键.
- 出于环境和安全原因,水性合成方法是首选的.
研究的目的:
- 开发一种新的,以水为基础的合成单分散银纳米立方体.
- 描述合成的纳米立方体的晶体结构和形态.
- 研究银纳米立方体在溶液和基板上的自我组装行为.
主要方法:
- 通过使用n-hexadecyltrimethylammonium bromide (HTAB) 在120°C的修饰银镜反应进行合成.
- 使用电子显微镜和X射线衍射进行表征,以确认尺寸,形状和晶体结构.
- 在水溶液和各种基板上进行稳定性和自我组装研究.
主要成果:
- 在水中首次合成了单分散的银纳米立方体 (55 ± 5 nm边长).
- 证明每个纳米立方体是一个单晶,有6个面.
- 观察到纳米立方体形成稳定的水溶液,并表现出自我组装成2D数组,在基板上有规律的检查模式.
结论:
- 建立了一个简单有效的单分散银纳米立方体的水性合成路径.
- 合成的银纳米立方体具有明确的晶体结构和理想的溶液稳定性.
- 观察到的自组装成2D阵列为等离子体和传感领域的应用提供了可能性.
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