Bis-Naphthylacrylonitrile-Based Supramolecular Artificial Light-Harvesting System for White Light Emission

Abstract

A novel aggregation-induced emission (AIE)-based artificial light-harvesting system (LHS) is successfully assembled via the host-guest interaction of bis-naphthylacrylonitrile derivative (BND), water-soluble pillar[5]arene (WP5), and sulforhodamine 101 (SR101). After host-guest assembly, the formed WP5⊃BND complexes spontaneously self-aggregated into WP5⊃BND nanoparticles (donors) and SR101 (acceptors) is introduced into WP5⊃BND to fabricate WP5⊃BND-SR101 LHS. Through the investigation of energy transfer between donors and acceptors, the artificial light-harvesting processes are certified in WP5⊃BND-SR101 LHS and the absolute fluorescence quantum yields (Φ_f(abs)) are significantly improved from 8.9% (for WP5⊃BND) to 31.1% (for WP5⊃BND-SR101), exhibiting the excellent light-harvesting capabilities. Notably, by tuning the donor/acceptor (D:A) molar ratio to 250:1, a conspicuous white light emission (CIE coordinate is (0.32, 0.32)) is realized and the fluorescence quantum yield of white light emission (Φ_{f(abs)WP5⊃BND-SR101-White}) is 29.2%. Moreover, the antenna effect of white fluorescence emission (AE_{WP5⊃BND-SR101-White}) can reach 36.2, which is higher than that of recent artificial LHSs in water environments, suggesting vast potential applications in aqueous LHSs.