Thermoresponsive artificial light-harvesting system with temperature-gated cascade energy transfer and photocatalysis

Abstract

Natural photosynthesis elegantly coordinates energy transfer, energy conversion, and environmental responsiveness within complex supramolecular frameworks. Replicating this multifunctionality in artificial systems remains a formidable challenge. In this work, we report a biomimetic light-harvesting system (LHS) constructed through the self-assembly of an amphiphilic molecule, TPE-CSO, which integrates aggregation-induced emission (AIE)-active tetraphenylethylene and cyanostilbene chromophores with oligo(ethylene glycol) segments. The resulting nanostructures act as efficient energy donors and exhibit thermoresponsive disassembly behavior above their lower critical solution temperature (LCST). By co-assembling TPE-CSO with two fluorescent acceptor dyes, Rh6G and SR101, we established a cascade Förster resonance energy transfer (FRET) network that boosts reactive oxygen species (ROS) generation in a temperature-dependent manner. This adaptive LHS functions as a thermosensitive photocatalyst, efficiently promoting the oxidative cleavage of 1,1-diphenylethylene derivatives with yields reaching 93%. Notably, the catalytic performance diminishes at elevated temperatures, mimicking the temperature vulnerability observed in natural photosynthetic systems. This multifunctional system represents a significant step toward biomimetic light-harvesting platforms with built-in environmental adaptability.