Supramolecular Sequential Light‐Harvesting Systems for Constructing White LED Device and Latent Fingerprint Imaging

The fabrication of supramolecular light‐harvesting systems (LHS) with sequential energy transfer is of significance in utilizing light energy. In this study, we report the non‐covalent self‐assembly of a sequential LHS by pillar[5]arene‐based host‐guest interaction in water and its applications in white light‐emitting diode (LED) device and latent fingerprint imaging. The host‐guest complex WP5 ⊃ ${ \supset }$ G self‐assembles into nanoparticles in water and shows enhanced aggregation‐induced emission (AIE) effect. The nanoparticles can be further used to construct sequential LHS with fluorescent dyes 4,7‐di(2‐thienyl)‐benzo[2,1,3]thiadiazole (DBT) and sulforhodamine 101 (SR101). Impressively, the system shows white‐light emission when the molar ratio of WP5 ⊃ ${ \supset }$ G/DBT/SR101 is 1100/2/16. The material can be coated on a LED bulb to achieve white‐light emission. In addition, the sequential LHS exhibit multicolor fluorescence including red emission, which have been successfully applied to high‐resolution imaging of latent fingerprints. Therefore, we demonstrated a general strategy for the construction of sequential LHS in water based on macrocyclic host‐guest interaction and explored its multi‐functional applications in white‐light LED device and imaging of latent fingerprints, which will promote future development and application of supramolecular LHSs. Based on the non‐covalent self‐assembly of water‐soluble pillar[5]arenes, using WP5⸧G as the energy donor and commercially available dyes DBT (acceptor I) and SR101 (acceptor II) as the energy acceptor, a supramolecular light‐harvesting system with sequential energy transfer was successfully constructed. Significantly, this system shows attractive applications in white light‐emitting diode (LED) devices and latent fingerprint (LFP) imaging.