Circularly polarized luminescence from chiral macrocycles and their supramolecular assemblies

Circularly polarized luminescence (CPL) materials have attracted significant attention in recent years owing to their potential application prospects in advanced display technologies, information encryption, polarization-based imaging, etc. The rational design, synthesis and assembly of chiral luminescent molecular architectures are some of the most efficient strategies for the fabrication of new CPL materials. Compared with conventional non-cyclic chiral building blocks, chiral macrocycles are unique in terms of their well-defined molecular geometries, guest-encapsulation and hierarchical self-assembly capabilities. In this review, we summarize the research progress in chiral macrocycle-based CPL systems and show how chiral macrocycles can be further used to self-assemble and manipulate CPL activities. This review mainly includes three sections based on the utilization approaches of chiral macrocycles, as follows: (1) CPL from individual chiral macrocycles; (2) CPL from the host-guest complexes of chiral macrocycles; and (3) CPL from the self-assemblies of chiral macrocycles. It is unveiled that the chiral macrocycle-related host-guest complexes and their self-assembled nanoarchitectures can be good candidates as CPL emitting materials.