Circularly polarized phosphorescence and photon transport of micro/nanocrystals of ruthenium and iridium complexes with chiral anions

Materials with efficient circularly polarized phosphorescences (CPPs) are of potential use in advanced data encryption and anti-counterfeiting, bioimaging, optoelectronic devices and so forth. Herein, a simple method is presented for the preparations of CPP-active micro/nanocrystals with large luminescence dissymmetry factors ( g lum ), high phosphorescence quantum efficiencies ( Φ p ) and tunable emission colors. Diastereomeric Ir III and Ru II complexes with chiral (±)-camphorsulfonate counter-anions are readily synthesized and assembled into crystalline microrods, microplates or nanofibers with ordered morphologies. The chir-ality information of chiral counter-anions is efficiently transferred to the metal components to afford CPPs with cyan, green, yellow, or red emission colors and Φ P in the range of 5%–85%. The number of chiral anions is found to play a role in influencing the CPP magnitudes of these crystals. The dicationic Ru II and tricationic Ir III complexes show g lum values in the 10 −2 order, which are much larger with respect to those of monocationic Ir III complexes. Single crystal X-ray analysis is performed to obtain information on the chirality transfer of these materials. In addition, circularly polarized photonic signal waveguiding is demonstrated using the microcrystals of an Ir III complex. This work demonstrates an appealing strategy of constructing chiral micro/nano-architectures for potential applications in chiral nanophotonics.