Conformation-Induced Dynamic Circularly Polarized Luminescence in Platinum(II) Rotor-Doped Cholesteric Liquid Crystals for Time-Encoded Encryption.

Constructing phototunable cholesteric liquid crystals (CLCs) systems with facile fabrication, fast response, and high circularly polarized luminescence (CPL) dissymmetry remains a great challenge for achieving multilevel information encryption and advanced anticounterfeiting technologies. Herein, we report a conformation-driven dynamic CLCs system based on a cyclometalated platinum(II) rotor and a chiral inducer dispersed in a nematic host. By varying the doping concentration, two distinct systems are obtained with monomer-dominated green emission at 1.0 wt % exhibiting a |glum| of 0.8 and aggregate-dominated yellow emission at 2.5 wt % achieving a remarkable |glum| of 1.5, demonstrating that a single luminophore enables color-tunable high-dissymmetry CLCs without the need for multiple components. Upon alternating 420 irradiation and dark period, the orthogonal molecular geometry of the rotor undergoes reversible conformational changes, disrupting the helical ordering and inducing isothermal cholesteric-to-isotropic phase transitions that enable reversible CPL switching. Leveraging these synergistic features, including phototriggered phase behavior and switchable CPL with high dissymmetry, we demonstrate rewritable patternings, and multilevel information storage and encryption, offering a versatile platform for next-generation secure optical technologies.