Self-Assembly of Chiral Nematic-Like Films with Chiral Nanorods Directed by Chiral Molecules

Chiral superstructures are ubiquitous in nature and display intriguing and elegant performances, which inspired us to realize multiscale chiral mesostructured inorganics. Here, we report cholic acid-induced anisotropic epitaxial growth of chiral CdSe/CdS nanorods (CCCNs) and their self-assembly into chiral nematic-like films (CNFs) via an evaporation-induced self-assembly route. Three levels of chirality exist in the CNFs assembled with CCCNs: a primary chiral distortion of the nanorod, a secondary chiral nematic-like phase in which layered nanobelts are stacked to form with a side-by-side arrangement of the CCCNs, and tertiary helical planks with stacking of the layered chiral nematic-like phase creating a banded spherulite structure. The CNFs exhibited excitonic absorption- and scattering-based optical activities and circularly polarized luminescence due to their hierarchical chirality.