用醇覆盖的CdTe纳米晶体的光学活性和奇拉性记忆
Takuya Nakashima1, Yuki Kobayashi, Tsuyoshi Kawai
1Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan. ntaku@ms.naist.jp
Journal of the American Chemical Society
|July 11, 2009
概括
合体连接体在化纳米晶体 (CdTe NC) 中创建镜像圆形二元化特征. 这种奇拉性即使在连接物交换后也持续存在,这表明纳米材料中有一种新的奇拉性记忆效应.
科学领域:
- * 纳米技术的使用
- * 材料科学 材料科学
- * 有机化学 有机化学
背景情况:
- *电 (CdTe) 纳米晶体 (NCs) 是具有可调节光学和电子性能的半导体纳米粒子.
- * 奇拉性或"手性"是分子系统中的关键性质,影响生物活动和材料特性.
- * NCs与奇拉分子的表面被动化是赋予特定功能的关键策略.
研究的目的:
- *为了合成和表征CdTeNCs被特定的性带被动化.
- * 调查这些合性CdTeNC中的光学活动的起源.
- * 为了探索连接物交换后的表面性稳定性和持久性.
主要方法:
- *使用已知的体化学方法合成CdTeNCs.
- *通过d-和l-cysteinemethylester化物对CdTeNCs进行被动化.
- *使用循环二重化 (CD) 光谱法进行表征,以评估光学活动.
- * 用Achiral thiols进行联结物交换实验.
主要成果:
- * CdTe NC 呈现出明显的 CD 配置文件,根据封装配体的性,作为镜像.
- * 光学活性归因于硫化物 (CdS) 的扭曲外,其中包含了性封闭分子.
- *即使用阿基拉性醇取代了奇拉性联结物,也保留了表面奇拉性,这表明了奇拉性记忆效应.
结论:
- * 状配体有效诱导和控制CdTeNCs的光学活动.
- * 扭曲的CdS外在观察到的奇拉性中起着关键作用.
- * CdTe NC 显示出显著的性记忆效应,对性感知和不对称催化有意义.
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