通过电子和连贯振动光谱仪确定的CdSe量子点中的表面放大连接体障碍
Matthew T Frederick1, Jennifer L Achtyl, Kathryn E Knowles
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|April 26, 2011
概括
在化量子点 (QD) 上的分子排序随着QD大小的减少而减少,这与表面曲率有关. 这一发现为QD片中的分子顺序提供了化学控制.
科学领域:
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
- 纳米技术纳米技术
背景情况:
- 体量子点 (QD) 在光电子学中至关重要.
- 控制QD表面上的连接物排序会影响薄膜的特性.
- 了解尺寸依赖排序是QD应用程序的关键.
研究的目的:
- 测量CdSe QDs上的内部和分子间带排序.
- 为了调查这个订单对QD大小的依赖性.
- 为了将连接体顺序与底层 (Cd2+) 的顺序相关联.
主要方法:
- 振动总频率生成 (SFG) 光谱检测有机连接物顺序.
- 在X射线光电子光谱学 (XPS) 测量线宽,用于Cd(2+) 顺序.
- 合成不同大小的CdSe量子点.
主要成果:
- 随着QD半径的减少,连接体的顺序会下降.
- 这种下降与QD半径>2.4纳米的减少Cd(2+) 顺序相关.
- 对于 QD 半径 < 2.4 nm,联结体顺序的减少归因于表面曲率的增加.
结论:
- 较小的QD的表面曲率增加了带障碍.
- Cd(2+) 障碍是由合成诱导的Cd(2+) -表面活性物复合物引起的.
- 通过修改表面活性剂混合物,可以实现对QD膜中的分子顺序的化学控制.
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