Full-Color and White Circularly Polarized Luminescence of Hydrogen-Bonded Ionic Organic Microcrystals

A simple and general method is presented herein for the in situ preparations of circularly polarized luminescence (CPL)-active microcrystals with a large luminescence dissymmetry factor g(lum), high fluorescence quantum efficiency (phi(FL)), wide emission color tenability, and well-ordered morphology. The reactions of pyridine-containing achiral molecules 1-7 with chiral camphor sulfonic acid ((+/-)-CSA) gave crystalline microplates formed by hydrogen bonding interactions between the protonated pyridinium units and the sulfonic anions. The chiral information of CSA are effectively transferred to the microcrystals by hydrogen bonding to afford full-color CPL from deep-blue to red with g(lum) in the order of 10(-2) and phi(FL) up to 80 %. Moreover, organic microcrystals with high-performance white CPL (phi(FL)=46 %; |g(lum)|=0.025) are achieved via the light-harvesting energy transfer between blue and yellow emitters.

Automated summary

This paper proposes a simple method for in situ preparation of circularly polarized luminescence (CPL)-active microcrystals, which achieves control of luminescence dissymmetry through hydrogen bonding interactions between molecules, allowing for tunable emission colors, ordered morphology, and high luminescence efficiency.