Polarized light plays a crucial role in advanced visual perception by providing valuable information regarding surface shape and local curvature as visual features. Among various polarized light phenomena, Circularly Polarized Luminescence (CPL) refers to the emission of chiral luminophores under excitation, resulting in unequal emission of left- and right-handed polarized light. Due to these properties, CPL has tremendous potential applications in 3D displays, optical information processing and storage, molecular switches, bio-detection, and chiral sensors. Therefore, it is of paramount importance, both in terms of elucidating the emission mechanisms and designing novel chiral materials, to construct supramolecular systems with CPL characteristics. However, achieving supramolecular assemblies with high dissymmetry factors (glum) and multicolor (especially white) CPL emission poses a significant challenge.

  Recently, the research group reported a novel strategy for the hierarchical self-assembly of supramolecular helical nanowires (SHNWs) with a glum value of 6.8×10-3 and white CPL emission using supramolecular coordination polymers (SCPs). Firstly, SCPs were formed through the metal coordination of the M1 monomer containing a chiral center and a diimide derivative, and the M2 monomer functionalized with triphenylamine and Eu3+. Subsequently, the SCPs underwent a time-dependent hierarchical self-assembly process to yield the SHNWs. These SHNWs achieved chiral amplification and exhibited high glum values in solution. Notably, the color of their CPL emission could be effectively tuned from blue to red, ultimately achieving white CPL emission. As a result, this study provides an effective approach for the preparation of supramolecular materials with high dissymmetry factors and white-light CPL.

Schematic illustration of supramolecular polymer hierarchical assembly with adjustable color and white light CPL emission.

The research findings were published in "Chemical Communications" (Chem. Commun., 2022, 58, 4647-4650).

Link to the paper: https://pubs.rsc.org/en/content/articlepdf/2022/cc/d2cc00336h.