Liu Yuanyuan, Rowell Nelson, Willis Maureen, Zhang Meng, Wang Shanling, Fan Hongsong, Huang Wen, Chen Xiaoqin, Yu Kui
Institute of Atomic and Molecular Physics , Sichuan University , 610065 Sichuan , P. R. China.
Metrology Research Centre , National Research Council Canada , Ottawa , Ontario K1A 0R6 , Canada.
J Phys Chem Lett. 2019 Jun 6;10(11):2794-2801. doi: 10.1021/acs.jpclett.9b00838. Epub 2019 May 14.
Reports on photoluminescent colloidal semiconductor two-dimensional (2D) helical nanostructures with one-dimensional quantum confinement are relatively rare. Here, we discuss the formation of such photoluminescent nanostructures for CdSe. We show that when as-synthesized unpurified zero-dimensional (0D) CdSe magic-size clusters (MSCs) (passivated by carboxylate ligands with three-dimensional quantum confinement) are dispersed in a solvent (such as toluene or chloroform) containing hexadecylamine and then subjected to sonication, helical nanostructures are obtained, as observed by transmission electron microscopy. We demonstrate that the formation involves the self-assembly of 0D MSCs into 2D nanoplatelets, which act as intermediates. The CdSe MSCs and their self-assembled 2D nanostructures display almost identical static optical properties, namely, a sharp absorption doublet with peaks at 433 and 460 nm and a narrow emission peak at 465 nm; this is a subject for further study. This study introduces new methods for fabricating photoluminescent helical nanostructures via the self-assembly of photoluminescent MSCs.
关于具有一维量子限制的光致发光胶体半导体二维（2D）螺旋纳米结构的报道相对较少。在此，我们讨论了CdSe这种光致发光纳米结构的形成。我们表明，当合成后未经纯化的零维（0D）CdSe魔法尺寸团簇（MSCs）（被具有三维量子限制的羧酸盐配体钝化）分散在含有十六胺的溶剂（如甲苯或氯仿）中，然后进行超声处理时，通过透射电子显微镜观察到会得到螺旋纳米结构。我们证明该形成过程涉及0D MSCs自组装成二维纳米片，这些纳米片作为中间体。CdSe MSCs及其自组装的二维纳米结构表现出几乎相同的静态光学性质，即具有在433和460 nm处的尖锐吸收双峰以及在465 nm处的窄发射峰；这是一个有待进一步研究的课题。本研究介绍了通过光致发光MSCs的自组装来制造光致发光螺旋纳米结构的新方法。
