Chirality-Driven Left-Handed Helical Nanofibers with Amplified CPL Emission via Helicoidal Aggregation of Bulky Naphthalimide AIEgens.

We report the preparation of left-handed helical fibers, imaged by scanning electron microscopy, with enhanced circularly polarized luminescence (CPL) signals, by the self-assembly of chiral naphthalimide derivatives bearing chiral urea moieties, which exhibit aggregation-induced emission luminescence (AIE) in mixtures of organic solvents with high water content. The helical fibers are driven by specific molecular interactions, the particular geometry of the core dye, and the inherent chirality of the substituents. Notably, enantiomeric pairs (R,R and S,S) of the NMI derivatives displayed mirror-image circular dichroism (CD) signals but both emitted circularly polarized luminescence (CPL) of the same handedness, attributed to the supramolecular interactions at the aggregated state. Furthermore, these organic left-handed fibers served as chiral templates for the growth of silver nanoparticles. The metallization process was confirmed by elemental analysis using energy-dispersive X-ray spectroscopy (FESEM-EDX). This work highlights a strategy for the rational design of chiral aggregation-induced emission luminogens and their use as scaffolds for the synthesis of metal coverings.