Institute of Atomic and Molecular Physics, Sichuan University, 610065, Chengdu, PR China.
School of Materials Science and Engineering, Huazhong University of Science & Technology, 430074, Wuhan, PR China.
Nat Commun. 2018 Jun 27;9(1):2499. doi: 10.1038/s41467-018-04842-0.
Structural isomerism of colloidal semiconductor nanocrystals has been largely unexplored. Here, we report one pair of structural isomers identified for colloidal nanocrystals which exhibit thermally-induced reversible transformations behaving like molecular isomerization. The two isomers are CdS magic-size clusters with sharp absorption peaks at 311 and 322 nm. They have identical cluster masses, but slightly different structures. Furthermore, their interconversions follow first-order unimolecular reaction kinetics. We anticipate that such isomeric kinetics are applicable to a variety of small-size functional nanomaterials, and that the methodology developed for our kinetic study will be helpful to investigate and exploit solid-solid transformations in other semiconductor nanocrystals. The findings on structural isomerism should stimulate attention toward advanced design and synthesis of functional nanomaterials enabled by structural transformations.
胶体半导体纳米晶体的结构异构性在很大程度上尚未得到探索。在这里，我们报告了一对结构异构体，它们是胶体纳米晶体的结构异构体，表现出类似于分子异构化的热诱导可逆转变。这两种异构体是 CdS 魔角团簇，在 311nm 和 322nm 处有尖锐的吸收峰。它们具有相同的团簇质量，但结构略有不同。此外，它们的相互转化遵循一级单分子反应动力学。我们预计这种异构动力学适用于各种小尺寸功能纳米材料，并且我们为动力学研究开发的方法将有助于研究和开发其他半导体纳米晶体中的固-固转变。关于结构异构性的发现应该会引起人们对通过结构转变实现的功能纳米材料的高级设计和合成的关注。
