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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. [ABSTRACT FROM AUTHOR]

Organic luminescent materials with time‐dependent emission colors show promising applications in the fields of chemical sensing, high‐resolution bioimaging, and high‐security information encryption. Herein a time‐dependent fluorescence system based on a spirocyclic scaffold‐bridged cyanostilbene dimer (SDCS) as the single component in a mixed CH3CN/H2O solvent is presented. Specifically, the original orange‐emitting nanoparticles prepared from SDCS by reprecipitation can transform into green‐emitting nanosheets over time driven by supramolecular self‐assembly. It is worth noting that such a transformation rate can be controlled by tuning the water fraction. Based on these unique properties, fluorescent binary codes are developed, enabling time‐dependent information encryption with a higher level of security. Moreover, the dual color can be individually fixed by solid matrices such as hydrogel or powder. The obtained luminescent powders are successfully used in two‐color fluorescence imaging of latent fingerprints. This work demonstrates the use of a supramolecular strategy to control multiple emissions in a single‐component system for multifunctional applications. [ABSTRACT FROM AUTHOR]

A guest molecule containing a short alkyl spacer between the tetraphenylethylene group and the methylpyridinium group was designed and synthesized. After complexation with a water‐soluble pillar[5]arene, the resulting host‐guest complex can further self‐assemble into fluorescence‐emitting nanoparticles in water. By loading a commercially available dye Rhodamine 6G into the nanoparticles, an efficient artificial light‐harvesting system with high donor/acceptor ratios (>400/1) was successfully constructed. The obtained systems show considerable antenna effects with values of more than 10 times. The system also exhibits tunable fluorescence emission behavior and can be used as a fluorescent ink for information encryption. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE) materials have attracted increasing research interest in recent years due to their excellent fluorescence properties in an aggregated state. Concurrently, anion coordination interactions have played a key role in the development of supramolecular assemblies and sensors. In the past decade, investigations towards fluorescent materials or sensors based on AIE and anion coordination interactions are continuously being reported. In this minireview, we briefly summarize the burgeoning progress of AIE-based materials and sensors driven by anion coordination interactions. We believe that an increasing number of achievements in anion-coordination induced emission materials will appear in the near future and will demonstrate potential applications, including bio-imaging and bio-sensors. [ABSTRACT FROM AUTHOR]

Responsive fluorescent nanomaterials have been received considerable attention in recent years. In this work, a bola‐type amphiphilic molecule, CSO, was synthesized which contains a hydrophobic cyanostilbene core and hydrophilic oligo(ethylene glycol) (OEG) coils at both sides. The cyanostilbene group is aggregation‐induced emission (AIE) active, while the OEG coils are thermo‐responsive. As a result, the CSO molecules can self‐assemble into blue‐fluorescent nanoassemblies with lower critical solution temperature (LCST) behavior in aqueous media. It is noteworthy that the LCST behavior can be reversibly regulated with changes in concentration and the introduction of K+. Intriguingly, fluorescence of CSO assembly shows a blue‐shift upon heating. Finally, by employing CSO as a light capturing antenna and energy donor, an artificial light harvesting system with tunable emission and thermo‐responsive characteristics was fabricated. This study not only demonstrates an integrated approach to create responsive fluorescent nanomaterials, but also shows great potential for producing luminescent materials and mimicking photosynthesis in nature. [ABSTRACT FROM AUTHOR]

The development of stimuli‐responsive fluorescent materials in water based on organic molecule has drawn significant interest. Herein, we designed and synthesized an amphiphilic molecule M containing a fixed tetraphenylethylene moiety (FTPE) as hydrophobic part and tri(ethylene glycol) (TEG) chains as hydrophilic part. Notably, the FTPE moiety is aggregation‐induced emission (AIE) active, while the TEG chains are thermo‐responsive. M can self‐assemble into fluorescent nanoparticles (NPs) in water, which showed lower critical solution temperature (LCST) behavior. Moreover, its clouding point can be reversibly tuned upon the concentration variation. Interestingly, the NPs can be acted as a fluorescence thermometer in aqueous media owing to their unique AIE and LCST behaviors. Our work herein not only provides an integration strategy to construct stimuli‐responsive fluorescent materials but also shows great potential in biological applications including bioimaging and biosensors. [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]

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]