Research Progress of Circularly Polarized Room-temperature Phosphorescent Materials based on Chiral Supramolecular Assembly

Circularly polarized room-temperature phosphorescence (CP-RTP) materials have garnered significant attention due to their exceptional optical sensitivity and spatial resolution, making them highly promising for a wide array of applications, such as three-dimensional displays, anti-counterfeiting, and information storage.Generally, the polarization magnitude is quantified by the luminescence dissymmetry factor (glum), which has a value between -2 and 2. However, while chiral organic RTP materials often demonstrate higher luminous efficiency, they typically display remarkably low glum values, generally in the order of 10-5 to 10 -3 , owing to their inherently weak magnetic transition dipole moment.This limitation significantly hinders the practical application of high-performance CP-RTP materials.Therefore, enhancing the glum values of CP-RTP materials remains a substantial challenge.With the rapid advancement of chiral supramolecular assembly, researchers have discovered that this system can construct long-range ordered helical nanostructures by precisely regulating intermolecular interactions, such as π-π stacking and hydrogen bonding.This approach facilitates the attainment of a high glum value while maintaining favorable luminous efficiency.Meanwhile, the processes of chiral self-assembly or co-assembly frequently involve chiral transfer, chiral induction, and intermolecular Förster resonance energy transfer.These processes are advantageous for inducing achiral dyes to achieve CP-RTP.This dramatically simplifies the synthesis of CP-RTP materials, circumventing the often-complex and costly preparation of intrinsically chiral RTP chromophores.Consequently, chiral supramolecular assembly systems have emerged as a highly effective strategy for the development of CP-RTP materials exhibiting substantially improved glum values.This review comprehensively examines the influence of helical structures on the photophysical properties of chiral supramolecular assembly systems, summarizing recent progress in the design, synthesis, and application of chiral supramolecular RTP materials, with a particular focus on their exploitation in advanced information encryption and anti-counterfeiting technologies.We delve into the underlying mechanisms driving enhanced circular polarization and discuss future directions for this rapidly evolving field.