Stable Deep-Blue Photoluminescence from Photoirradiated Cyanobiphenyl Liquid Crystals

Abstract

Deep-blue photoluminescence with high quantum yield (Φ = 0.516) is demonstrated from cyanobiphenyl liquid crystals under deep-UV irradiation (310 nm). The emission arises intrinsically from the liquid crystalline phase via excimer excitation, exhibits distinct polarization reflecting molecular alignment, and shows remarkable long-term stability -offering a simple platform for polarized soft photonic materials.Cyanobiphenyl-based liquid crystals (LCs) represent one of the most fundamental and extensively studied molecular series in LC science. [1][2][3][4][5] Since their introduction, n-cyanobiphenyls such as 4-cyano-4′-pentylbiphenyl (5CB) have served as standard model compounds for investigating the basic physics and chemistry of LC phases. 6 From classical Schlieren texture observations to detailed investigations of nematic-isotropic phase transitions, this series has played a central role in establishing the fundamental understanding of molecular alignment, elastic properties, and phase behavior of thermotropic LCs.