Aggregation-Induced Emission Carbon Dot-Based Multicolor Circularly Polarized Afterglow with a High Luminescence Dissymmetry Factor

Abstract

Carbon dots (CDs) with circularly polarized afterglow (CPA) materials have drawn increasing attention as cutting-edge research in the field of chiral luminescence owing to their promising applications in various fields. However, due to the weak optical activity of chiral CDs and the limited afterglow color of phosphorescent CDs, it is still a formidable challenge to construct multicolor CD-based CPA materials with a high luminescence dissymmetry factor (g_lum). Herein, positively charged aggregation-induced emission (AIE) CDs were prepared using dithiosalicylic acid and ionic liquid as precursors. Encapsulating the positively charged AIE CDs in the chiral nematic structure of negatively charged cellulose nanocrystal (CNC) films enabled the production of a surprising warm white CPA with g_lum up to −0.16. To further expand the color of afterglow, the phosphorescence resonance energy transfer between CDs and commercial fluorescent dyes was constructed in CNC films. Finally, the potential applications in advanced dynamic information encryption were explored by virtue of the different afterglow lifetimes.