Dual‐Handed Circularly Polarized Luminescence from Polymer Fiber‐Confined and Stabilized Perovskite Nanocrystals in Hydrated Liquid Crystals

Abstract Circularly polarized luminescence (CPL) is of interest for optical encryption and anticounterfeiting applications. However, achieving dual‐handed CPL emission from perovskite nanocrystals (PNCs) in hydrated chiral liquid crystal systems remains a challenge because of their susceptibility to water‐induced degradation and disruption of liquid crystal ordering. These issues limit luminescence efficiency, structural integrity, and chiroptical control. Here, a confinement strategy is presented using polymer‐encapsulated perovskite nanofibers, which isolate PNCs from water while supporting the in situ self‐assembly of cellulose nanocrystals into a cholesteric photonic framework. The resulting solid‐state composite achieves high photoluminescence quantum yield (65.56%), mechanical strength (32.15 MPa), and a broad dissymmetry factor range (g lum from −0.96 to +0.49) from a single left‐handed cholesteric structure. Importantly, by engineering the reflectivity of asymmetric bilayer architectures, the composite exhibits enhanced dual‐handed CPL emission depending on the viewing direction. The multimodal optical properties demonstrated here highlight the potential of this system in optical encryption and anticounterfeiting applications.