Aggregation-Induced\nEmission Carbon Dot-Based Multicolor\nCircularly Polarized Afterglow with a High Luminescence Dissymmetry\nFactor

Carbon\ndots (CDs) with circularly polarized afterglow\n(CPA) materials\nhave drawn increasing attention as cutting-edge research in the field\nof chiral luminescence owing to their promising applications in various\nfields. However, due to the weak optical activity of chiral CDs and\nthe limited afterglow color of phosphorescent CDs, it is still a formidable\nchallenge to construct multicolor CD-based CPA materials with a high\nluminescence dissymmetry factor (<i>g</i><sub>lum</sub>).\nHerein, positively charged aggregation-induced emission (AIE) CDs\nwere prepared using dithiosalicylic acid and ionic liquid as precursors.\nEncapsulating the positively charged AIE CDs in the chiral nematic\nstructure of negatively charged cellulose nanocrystal (CNC) films\nenabled the production of a surprising warm white CPA with <i>g</i><sub>lum</sub> up to −0.16. To further expand the\ncolor of afterglow, the phosphorescence resonance energy transfer\nbetween CDs and commercial fluorescent dyes was constructed in CNC\nfilms. Finally, the potential applications in advanced dynamic information\nencryption were explored by virtue of the different afterglow lifetimes.