Time-Evolving Reversible Circularly Polarized Luminescence Enabled by Light-Fueled Dissipative Self-Assembly of...

The development of smart circularly polarized luminescence (CPL) materials faces significant challenges, primarily centered on achieving high luminescence dissymmetry factors (g_lum) alongside broadly tunable responses. Here, we report a chiral scaffold based on covalent organic frameworks (COFs) for high-performance and adaptive photocontrollable time-evolving CPL, enabling identifiable and encrypted chiroptical outputs. Cyclodextrin modified on the COF generates multicolor CPL emission through noncovalent interaction with fluorophores. Blending the modified COF and fluorophores with polyethylene glycol (PEG) yields transparent mixed-matrix films exhibiting a high g_lum of -0.027 and absolute quantum yield (39%). Subsequently, sulfonato-merocyanine, a photochromic switch, is introduced to modulate the system's emission, endowing the reversible CPL signals with light-fueled tunability and time-dependent dynamic evolution. Notably, we fabricate mixed-matrix films to amplify the light-controllable CPL signals, where the g_lum varies between -0.009 and -0.044 upon 420 nm irradiation and thermal relaxation. A dynamic modulation range of g_lum ≈0.035 is achieved, which is a remarkable value reported among dynamic COF-based CPL materials. Furthermore, films featuring photocontrollable, self-erasable vector luminescent signals are achieved for dual-mode anticounterfeiting. This work provides insight into the design of intelligent luminescent materials.