基终端表面:用于量子点的功能化和衍生性的新反应平台
Tapas K Purkait1, Muhammad Iqbal1, Muhammad Amirul Islam1
1Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada.
Journal of the American Chemical Society
|May 20, 2016
概括
合成的量子点 (SiQD) 具有氧终端表面,呈现出明亮的,大小依赖的光发光. 这些表面通过新交换反应进一步实现功能化,扩大SiQD应用.
科学领域:
- 材料科学
- 纳米技术
- 表面化学
背景情况:
- 量子点 (SiQD) 是具有可调节光电子特性的有前途的纳米材料.
- 表面功能化对于控制SiQD的溶解性,稳定性和进一步的修改至关重要.
- 现有的SiQD表面修饰方法可能很复杂或需要严苛的条件.
研究的目的:
- 开发一种简单的合成alkoxy终结SiQD的方法.
- 为了进一步表面功能化,研究基终端SiQD的配体交换能力.
- 探索合成的SiQDs的光发光特性.
主要方法:
- 在微波照射和室温条件下对化物终端SiQD (H-SiQD) 进行化.
- 使用BH3·THF用基或基替换基交换反应.
- 使用质子核磁共振 (1H NMR),富里埃变换红外 (FTIR) 和X射线光电子光谱 (XPS) 的表征.
主要成果:
- 基终结SiQD成功合成,在有机溶剂中具有可溶性和体稳定性.
- 合成的SiQD呈现出明亮的,大小依赖的光发光.
- 证实了前所未有的配体交换反应,允许用基或基替换基表面组.
结论:
- 这样可以直接合成基终结的SiQD.
- 基功能化SiQD作为通过配体交换进行后续表面修饰的多功能平台.
- 这些发现为在光电子和传感领域的各种应用量身定制SiQD特性开辟了新的途径.
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