Acetal-based spirocyclic skeleton bridged tetraphenylethylene dimer for light-harvesting in water with ultrahigh antenna effect.

Herein an aqueous-phase artificial light-harvesting platform has been constructed based on the self-assembly of three small organic molecules: a rigid acetal-based spirocyclic skeleton bridged tetraphenylethylene dimer as donor, a hydrophobic dye molecule Nile Red as acceptor, and the surfactant cetyltrimethyl ammonium bromide as amphiphile to enwrap the donor and acceptor and disperse them in water. Due to the rigid skeleton of the tetraphenylethylene dimer that can well accommodate and distribute Nile Red inside the self-assembled nanospheres, the system shows ultrahigh light-harvesting antenna effects. Moreover, by simply tuning the donor/acceptor molar ratio, tunable emission including a bright white-light emission could be realized. Image 1 • An efficient artificial light-harvesting system in water has been constructed by employing small organic molecules. • An ultrahigh antenna effect of 66 could be achieved under a higher donor/acceptor ratio of 250/1. • By simply adjusting the D/A ratio in the NPs, tunable emission including a white-light emission was achieved. • The system is also stable in the solid state and can be used as security inks for anti-counterfeiting techniques. [ABSTRACT FROM AUTHOR]