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Dynamic emissive materials in aqueous media have received much attention owing to their ease of preparation, tunable luminescence and environmental friendliness. However, hydrophobic fluorophores usually suffer from aggregation-caused quenching in water. In this work, we constructed an artificial light-harvesting system by using a non-covalent aggregation-induced emission dimer as antenna and energy donor. The dimer is quadruple hydrogen bonded from a ureidopyrimidinone derivative (M) containing a tetraphenylethylene group. The dispersed nano-assemblies based on the dimer in aqueous media were fabricated with the help of surfactant. By loading a hydrophobic acceptor molecule DBT into the nano-assemblies, man-made light-harvesting nanoparticles were fabricated, showing considerable energy transfer efficiency and a relatively high antenna effect. Additionally, the fluorescence color of the system can be gradually tuned by varying the content of the acceptors. This study provides a general way for the construction of an aqueous light-harvesting system based on a supramolecular dimer, which is important for potential application in luminescent materials. [ABSTRACT FROM AUTHOR]

The design and construction of an artificial light-harvesting system in water by mimicking the energy transfer cascade in natural photosynthesis are of significant importance. Herein, we report an efficient two-step sequential energy transfer system based on quadruple hydrogen-bonded supramolecular polymeric nanoparticles. By loading two types of hydrophobic dyes as energy acceptors, excitation energy from the supramolecular polymer could be funneled efficiently to the final acceptor through the relay acceptor. The system exhibits tunable multicolor emission from blue through yellow to red, as well as white light emission. [ABSTRACT FROM AUTHOR]

Efficient energy transfer is ubiquitous in natural light-harvesting systems (LHSs), which has inspired humans to develop various carrier platforms and energy transfer strategies to mimic nature. In this study, we employ pillar [5]arene-mediated nanoparticles as the nano-platform and a sequential energy transfer strategy to achieve a highly efficient LHS. Specifically, by incorporating the hydrophobic dye, eosin Y (ESY) into the nanoparticles as a relay acceptor, the excitation energy from the host-guest donor WP5 ⸧ G can be efficiently transferred to the final acceptor, sulforhodamine 101 (SR101), making the overall donor energy transfer efficiency up to 94%. Under this condition, the radiative rate constant (k r) of WP5 ⸧ G is almost 8 times higher, and the emission brightness (ε (λ abs) × φ F) is nearly doubled, indicative of the rapid and efficient energy transfer process. Finally, the as-prepared LHS nanoparticles were applied to LED devices to achieve color-tunable photoluminescence. This work demonstrates a fabrication strategy for highly efficient light-harvesting systems that holds great potential for manufacturing bright organic luminescent materials. [Display omitted] • A two-step light-harvesting system was successfully constructed. • The system was completely self-assembled in water phase. • The overall energy transfer efficiency of the donor is up to 94%. • The emission brightness after energy transfer was doubled. • The nanoparticles can be used to make photoluminescent devices. [ABSTRACT FROM AUTHOR]

Sequential energy transfer widely exists in natural light-harvesting systems (LHSs), which greatly benefits the full use of solar energy. In this work, we report an artificial light-harvesting platform derived from pillar (Wang et al., 2021) [5]arene-directed host-guest nanoparticles (WP5 ⊃ G) in aqueous media. The WP5 ⊃ G assembly can serve as a good donor owing to the excellent fluorescence behavior of G in the aggregated state, guaranteeing a two-step FRET from the WP5 ⊃ G to the relay acceptor eosin Y (ESY) and then to the final acceptor Nile red (NiR) to form a WP5 ⊃ G @ ESY / NiR system with high efficiency. As a consequence of the flexibility of the system, tunable emission including a highly efficient white-light emission can be realized. The WP5 ⊃ G @ ESY / NiR system was further used as a photocatalyst to catalyze dehalogenation reaction in aqueous solution, exhibiting remarkable catalytic activity as compared with the WP5 ⊃ G or ESY / NiR alone. [Display omitted] • A light-harvesting system based on self-assembly was successfully fabricated. • The system contains a stepwise energy transfer process. • The material is color tunable and a bright white-light emission was realized. • The material can be used as a photocatalyst for dehalogenation reaction. • The fabrication and application of the system were totally in an aqueous media. [ABSTRACT FROM AUTHOR]