揭示了氧化化学的潜力,以形成可调整大小,高指数的粒子
Megan A Parker1, Safa Khaddad1, Nicolas Fares2
1University of Bordeaux, CNRS, Bordeaux-INP, ICMCB, UMR 5026, F-33600 Pessac, France.
概括
化学家们开发了一种用于纳米粒子 (45-230 nm) 的新溶液合成方法. 这些可调节的颗粒具有很高的折射率,对先进的光学设备和光操纵应用有很大的希望.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 化学 化学 化学
背景情况:
- 75-200纳米范围内的粒子散射可见光,使其适合光学应用.
- 在这个尺寸范围内的颗粒的溶液合成一直是长期以来的一个挑战.
研究的目的:
- 为纳米粒子开发可控制的溶液相合成.
- 为了在粒子合成中实现尺寸可调性.
- 描述合成的颗粒的光学和表面特性.
主要方法:
- 在Zintl相 (Na4Si4) 和胺酸稳定Si(IV) 复合体之间发生溶液相反应.
- 粉末X射线衍射以确定连贯的域大小.
- 使用ToF-SIMS,FTIR和X射线光电谱的表面分析.
- 全息光学显微镜测量折射率.
主要成果:
- 通过调整反应剂比率,实现了45至230nm之间的颗粒的尺寸可调性.
- 晶石的大小在所有粒子大小中均,这表明聚合生长机制.
- 证实了颗粒表面上含有氨基酸结合体,初级氨基和被动氧化层的存在.
- 测量了个体颗粒在532nm的高折射率约为4.1的高折射率.
结论:
- 开发的溶液合成为可调整尺寸的纳米粒子提供了一条途径.
- 合成的粒子具有适用于可见光谱中强烈光散射的特性.
- 这些纳米粒子是光学设备和操纵的有希望的候选者.
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