Circularly polarized luminescence from supramolecular assemblies based on small molecules

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Photochemistry

Background:

• Chiral luminophores are traditionally used for circularly polarized luminescence (CPL)-active materials.
• Supramolecular assembly offers a novel strategy for CPL material development, expanding beyond chiral sources.
• Small molecule assembly provides better control compared to polymers for designing CPL materials.

Purpose of the Study:

• To review recent advancements in CPL from small-molecule assemblies.
• To compare three typical assembly modes, highlighting their differences, advantages, and disadvantages.
• To offer insights for the future development of chiroptical materials.

Main Methods:

• Systematic review of literature on small-molecule supramolecular assemblies for CPL.
• Analysis of assembly strategies focusing on chiral and achiral luminophores.
• Evaluation of performance enhancement, particularly the luminescence asymmetry factor (|g_lum|).

Main Results:

• Supramolecular assembly allows CPL materials from achiral species, increasing material diversity.
• This approach enhances CPL material performance, including the asymmetry factor.
• Small molecule assemblies offer controllable routes to advanced CPL materials.

Conclusions:

• Small-molecule supramolecular assembly is a powerful strategy for developing diverse and high-performance CPL materials.
• Understanding different assembly modes is crucial for optimizing CPL properties.
• This review provides a foundation for future innovations in chiroptical materials.