Design and Construction of an Artificial Light-Harvesting System Based on Polyacrylic Acid and a Cyanostilbene Derivative

The development of materials with tunable fluorescence properties is critical for advancing applications in sensing, imaging, and information encryption. In this study, we synthesized a cyanostilbene derivative (CSA) that combines the benefits of aggregation-induced emission (AIE) and self-assembly in water. CSA, featuring a cyanostilbene core and hydrophilic carboxylate groups, exhibits weak fluorescence in solution but forms highly fluorescent nanoaggregates (CSA-PAA) upon self-assembly with polyacrylic acid (PAA). By integrating rhodamine 6G (Rh6G) as an energy acceptor, we constructed a light-harvesting system (CSA-PAA-Rh6G) with high Förster resonance energy transfer (FRET) efficiency and tunable emission from green to yellow. This work presents a facile approach for the development of aqueous light-harvesting systems and shows promise for future applications in tunable luminescent materials.