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Organic optical heterostructures have emerged as promising candidates for applications in organic photonics. In this study, we demonstrate a facile strategy to integrate different emission and polarization properties into the sub-blocks of luminescent organic heterostructures, by a mask-assisted vapor treatment method on the microcrystals of a pyridine-functionalized tetraphenylethylene chromophore. [ABSTRACT FROM AUTHOR]

The integration of multiple functions within a single fluorescent molecule provides a promising platform for developing versatile, efficient, and cost‐effective materials with enhanced performance across diverse applications. In this study, we introduce TPEC, an aggregation‐induced emission (AIE) molecule derived from tetraphenylethylene‐based tetracarboxylate, which demonstrates multifunctional capabilities, including metal ion sensing and self‐erasable writing. TPEC exhibits amphiphilicity in water, self‐assembling into single‐layer nanosheets with robust blue fluorescence. Notably, the aqueous solution of TPEC displays a fluorescence colorimetric response to Al3+ ions and fluorescence quenching in the presence of Fe3+ ions. Additionally, TPEC powders undergo fluorescence colorimetric changes under mechanical stimulation, enabling self‐erasable writing on prepared paper. This study presents a straightforward strategy for the development of multifunctional luminescent materials based on the self‐assembly of a single‐component fluorophore. [ABSTRACT FROM AUTHOR]

Conventional synthetic methods of organic luminescent molecules often involve labor‐intensive solution‐phase organic synthesis, which violate the principles of atom‐economic transformation. Post‐synthetic modification (PSM) offers a promising alternative, allowing direct transformation from one fluorophore to another. Although PSM is commonly implemented in extended frameworks, its application in porous molecular crystals remains challenging. Herein, we focus on utilizing porous molecular crystals, specifically tetraphenylethylene‐cored frameworks, as versatile platforms for tandem PSM reactions to customize organic fluorophores. The tailored skeleton design ensures both the formation of porous structures and the occurrence of tandem solid‐solution phase reactions while maintaining the solid state of reactants and products in each step. The inherent non‐covalent bonding nature of the frameworks facilitates processing and characterization, offering unparalleled advantages for porous networks. The accompanying solid‐state fluorescence transition from green to blue and then to green (or yellow) enables real‐time monitoring of tandem reactions and provides intuitive mechanistic insights. This phenomenon is exploited for the facile construction of a dynamic information encryption system using fluorescent quick response codes. [ABSTRACT FROM AUTHOR]

Artificial light‐harvesting systems (LHSs) are of growing interest for their potential in energy capture and conversion, but achieving efficient fluorescence in aqueous environments remains challenging. In this study, a novel tetraphenylethylene (TPE) derivative, TPEN, is synthesized and co‐assembled with poly(sodium 4‐styrenesulfonate) (PSS) to enhance its fluorescence via electrostatic interactions. The resulting PSS⊃TPEN network significantly increased blue emission, which is further harnessed by an energy‐matched dye, 4,7‐di(2‐thienyl)benzo[2,1,3]thiadiazole (DBT), to produce an efficient LHS with yellow emission. Moreover, this system is successfully applied to develop color‐tunable light‐emitting diode (LED) devices. The findings demonstrate a cost‐effective and environmentally friendly approach to designing tunable luminescent materials, with promising potential for future advancements in energy‐efficient lighting technologies. [ABSTRACT FROM AUTHOR]

Dual‐state emission luminescent materials (DSEgens), which exhibit bright emissions in boththe solid state and solution, have been attracting research interest in the design of multifunctional materials.The delicate manipulation of molecular structures remains challenging in the synthesis of DSEgens. In this article, two novel molecules with dual‐state emission were synthesized by combining tetraphenylethylene with anthracene via dihydroisoxazole. Tetraphenylethylene acts as a solid‐state emitter, while the anthracene core functions as an emitter in the solution state to achieve DSE fluorescence properties. The THF/DCM mixture resulted in successfully obtaining the crystal structures of TPE−An−H and TPE−An−Cl. The quantum yields (QYs) of TPE−An−H were 31 % and 42 % in EA and the solid state, respectively, while TPE−An−Cl exhibited QYs of 32 % and 34 %. The novel synthesis method in this paper combines AIE with ACQ via dihydroisoxazole to achieve dual‐state emission, offering a new and concise approach. [ABSTRACT FROM AUTHOR]

A novel room‐temperature liquid crystal of tetraphenylethylene derivative (TPE‐DHAB) was synthesized using an ionic self‐assembly strategy. The TPE‐DHAB complex exhibits typical aggregation‐induced emission properties and a unique helical supramolecular structure. Moreover, the generation and handedness inversion of circularly polarized luminescence (CPL) can be achieved through further chiral solvation, providing a facile approach to fabricate room‐temperature liquid crystalline materials with controllable supramolecular structures and tunable CPL properties through a synergistic strategy of ionic self‐assembly and chiral solvation process. [ABSTRACT FROM AUTHOR]

Chirality and luminescence are important for both chemistry and biology, which are highly influenced by aggregation. In this work, a pair of metalated tetraphenylethylene(TPE)‐based organic cage enantiomers are reported, which feature a quadrangular prismatic cage structure. These homochiral cages exhibit concentration‐dependent chiral behaviors alongside a propensity for thermodynamic aggregation. Aggregation caused quench effect is found for these cages accompanying the increasing of the concentrations. When a poor solvent is added to produce a kinetical aggregation, the aggregation‐annihilation circular dichroism and aggregation‐induced emission behaviors are observed for these enantiomeric cages. By comparing these observations with the photophysical behaviors of a pair of structurally similar organic molecular enantiomers, the unique photophysical properties observed are intricately linked to the metal‐integrated TPE‐functionalized cage structures. [ABSTRACT FROM AUTHOR]

Picric acid is known as one of the most dangerous explosive materials and it has become one of the main pollutants in soil and, inter alia, groundwater. To date, many organic or inorganic probes have been reported to detect picric acid, especially in organic solvent systems. Nonetheless, the detection and adsorption of trace (sub-ppm or ppb level) picric acid in aqueous media remain challenging. Herein, we describe the facile synthesis of a tetraphenylethylene-based superphane cage via [6 + 2] condensation of dialdehyde and hexakis-amine, followed by a NaBH4–mediated reduction. This purely covalent organic cage was found able to show aggregation enhanced emission in a mixture of tetrahydrofuran and water (1:9, v/v), which can be utilised as a probe for detection of picric acid with ultrahigh sensitivity (as low as 0.9 ppb) and selectivity (against other tested nitroaromatic compounds). More importantly, this new superphane cage can serve as a new nonporous amorphous superadsorbent (NAS) material for adsorption of picric acid with an exceptional maximum uptake capability of 454 mg g−1. It also proved able to eliminate trace picric acid from aqueous media with up to 99% removal efficiency, meeting the discharge standard (<1.0 ppb). As such, we believe that this study offers new insight into the design and synthesis of NAS-based advanced materials for sensitive and selective detection and adsorption of trace pollutants from complex aqueous wastes. [ABSTRACT FROM AUTHOR]

This work designed and synthesized the first organic fluorescent sensor for lutein in aqueous solutions based on blue to yellow fluorescence change of thiosemicarbazide‐bridged bis‐tetraphenylene (Bis‐TPE). By condensing monohydroxy tetraphenylene derivatives with p‐phenylene di‐isothiocyanate, Bis‐TPE was produced. A fluorescence spectrophotometer was used to scan the fluorescence emission spectra from 380 to 700 nm with 360 nm as the excitation wavelength. The fluorescence spectra showed that Bis‐TPE exhibited high selective sensing ability for lutein in aqueous medium, and the fluorescence showed red‐shift phenomenon with a limit of detection as low as 0.26 μM for lutein. The sensing mechanism was confirmed by mass spectrometry, infrared, and fluorescence Job's plots based on the 1:1 stoichiometric ratio of double hydrogen bonding. The successful application of Bis‐TPE in sensing test strips means that Bis‐TPE can achieve efficient detection of lutein in complex environments. As a result, an aggregation‐induced luminescence‐based lutein fluorescence sensor was constructed, which exhibited highly selective and sensitive sensing of lutein, and provided a new research idea for the object detection of such structures. [ABSTRACT FROM AUTHOR]

Temperature and pressure sensors currently encounter challenges such as slow response times, large sizes, and insufficient sensitivity. To address these issues, we developed tetraphenylethylene (TPE)-doped polyvinylidene fluoride (PVDF) nanofiber membranes using electrospinning, with process parameters optimized through a convolutional neural network (CNN). We systematically analyzed the effects of PVDF concentration, spinning voltage, tip–to–collector distance, and flow rate on fiber morphology and diameter. The CNN model achieved high predictive accuracy, resulting in uniform and smooth nanofibers under optimal conditions. Incorporating TPE enhanced the hydrophobicity and mechanical properties of the nanofibers. Additionally, the fluorescent properties of the TPE-doped nanofibers remained stable under UV exposure and exhibited significant linear responses to temperature and pressure variations. The nanofibers demonstrated a temperature sensitivity of −0.976 gray value/°C and pressure sensitivity with an increase in fluorescence intensity from 537 a.u. to 649 a.u. under 600 g pressure. These findings highlight the potential of TPE-doped PVDF nanofiber membranes for advanced temperature and pressure sensing applications. [ABSTRACT FROM AUTHOR]

In this study, a novel multi‐stimulus responsive RGB fluorescent organic molecule, RTPE‐NH2, was designed and synthesized based on the combination of aggregation‐induced emission tetraphenylethylene (TPE) luminophore and acid‐responsive fluorescent molecular switch Rhodamine B. RTPE‐NH2 exhibits aggregation‐induced emission behavior, as well as UV irradiation‐stimulus and acid‐stimulus responsive fluorescence properties. It could emit orange‐red (R), green(G), and blue(B) light in both solution and PMMA film under 365 nm excitation. The dark through‐bond energy transfer (DTBET) mechanism was proposed and supported by control experiments and TD‐DFT calculations. The synthesis and application of RTPE‐NH2 could accelerate the development of organic smart materials with high sensitivity and excellent optical properties. [ABSTRACT FROM AUTHOR]

Monomers with low symmetries can form different topological structures in the preparation of organic two-dimensional (2D) materials. However, it remains challenging to modulate the topologies in practical synthesis. Leveraging theoretical insights into the formation energy of potential structural configurations, we report the topology modulation of a graphdiyne (GDY) derivative constructed from two-fold symmetric tetrakis(4-ethynylphenyl)ethene precursor by changing solvent combinations in a liquid-liquid interfacial system. An aqueous-organic (water-dichloromethane) interface afforded GDY with a kagome topology while a rhombic topology was formed at an organic-organic (hexane-acetonitrile) interface. A comprehensive evaluation of their structures and optoelectronic properties was conducted through various characterization techniques and theoretical computations. Our study provided new insights to modulate the topology of not only GDY but also other framework structures and obtain topologically pure materials in situations where different topologies are possible during practical synthesis. [ABSTRACT FROM AUTHOR]

Abstract Chirality and luminescence are important for both chemistry and biology, which are highly influenced by aggregation. In this work, a pair of metalated tetraphenylethylene(TPE)‐based organic cage enantiomers are reported, which feature a quadrangular prismatic cage structure. These homochiral cages exhibit concentration‐dependent chiral behaviors alongside a propensity for thermodynamic aggregation. Aggregation caused quench effect is found for these cages accompanying the increasing of the concentrations. When a poor solvent is added to produce a kinetical aggregation, the aggregation‐annihilation circular dichroism and aggregation‐induced emission behaviors are observed for these enantiomeric cages. By comparing these observations with the photophysical behaviors of a pair of structurally similar organic molecular enantiomers, the unique photophysical properties observed are intricately linked to the metal‐integrated TPE‐functionalized cage structures.

High-performance electrochromic (EC) and electrofluorochromic (EFC) materials have garnered considerable interest due to their diverse applications in smart windows, optoelectronics, optical displays, military camouflage, etc. While many different EC and EFC polymers have been reported, their preparation often requires multiple steps, and their polymer molecular weights are subjected to batch variation. In this work, we prepared two triphenylamine (TPA)-based and two tetraphenylethylene (TPE)-based derivatives functionalized with terminal styryl groups via direct Suzuki coupling with (4-vinylphenyl)boronic acid and vinylboronic acid pinacol ester. The two novel TPE derivatives exhibited green–yellow aggregation-induced emission (AIE). The EC and EFC properties of pre- and post-thermally treated derivatives spin-coated onto ITO–glass substrates were studied. While all four derivatives showed modest absorption changes with applied voltages up to +2.4 V, retaining a high degree of optical transparency, they exhibited obvious EFC properties with the quenching of blue to yellow fluorescence with IOFF/ON contrast ratios of up to 7.0. The findings therefore demonstrate an elegant approach to preparing optically transparent, heat-induced, cross-linkable styryl-functionalized EFC systems. [ABSTRACT FROM AUTHOR]

cis‐Linked cyclotetraphenylene dimer [2]c‐CTPE and trimer [3]c‐CTPE were synthesized via Pt‐mediated cyclization of cis‐diboronated tetraphenylethene. The structure of [2]c‐CTPE has been confirmed by single crystal X‐ray diffraction. The strain energy of [2]c‐CTPE and [3]c‐CTPE was calculated to be 86.28 ⋅ kJ mol−1 and 9.23 kJ ⋅ mol−1, respectively. [2]c‐CTPE and [3]c‐CTPE are typical AIEgens and show mechanofluorochromic properties. The comparisons of cis‐linked cyclotetraphenylenes with gem‐linked cyclotetraphenylenes were also discussed. [ABSTRACT FROM AUTHOR]

Two blue-emitting materials, 4-(12-([1,1′:3′,1″-terphenyl]-5′-yl)chrysen-6-yl)-N,N-diphenylaniline (TPA-C-TP) and 6-([1,1′:3′,1″-terphenyl]-5′-yl)-12-(4-(1,2,2-triphenylvinyl)phenyl)chrysene (TPE-C-TP), were prepared with the composition of a chrysene core moiety and terphenyl (TP), triphenyl amine (TPA), and tetraphenylethylene (TPE) moieties as side groups. The maximum photoluminescence (PL) emission wavelengths of TPA-C-TP and TPE-C-TP were 435 and 369 nm in the solution state and 444 and 471 nm in the film state. TPA-C-TP effectively prevented intermolecular packing through the introduction of TPA, a bulky aromatic amine group, and it showed an excellent photoluminescence quantum yield (PLQY) of 86% in the film state. TPE-C-TP exhibited aggregation-induced emission; the PLQY increased dramatically from 0.1% to 78% from the solution state to the film state. The two synthesized materials had excellent thermal stability, with a high decomposition temperature exceeding 460 °C. The two compounds were used as emitting layers in a non-doped device. The TPA-C-TP device achieved excellent electroluminescence (EL) performance, with Commission Internationale de L′Eclairage co-ordinates of (0.15, 0.07) and an external quantum efficiency of 4.13%, corresponding to an EL peak wavelength of 439 nm. [ABSTRACT FROM AUTHOR]

Achieving high luminescence dissymmetry factors and quantum yields in the solid state remains a significant challenge in developing circularly polarized luminescence (CPL) materials. This study presents the synthesis of double helices based on planar chiral [2.2]paracyclophane ([2.2]PCP) and tetraphenylethylene (TPE), which exhibit chiroptical and aggregation‐induced emission (AIE) properties. In particular, the double helix with long alkyl chains demonstrates tunable CPL activity driven by self‐assembly, exhibiting dissymmetry factors ranging from 10−4 to 10−2. Notably, doped PMMA films show an amplified dissymmetry factor of 0.058 and a high quantum yield of up to 51%. The designed molecules represent an ideal molecular functional material for generating efficient CPL with controllable dissymmetry factor and high emission efficiency in the solid state. This opens up possibilities for applications in chiroptical sensing, data storage, and light‐emitting devices based on solid‐state materials. [ABSTRACT FROM AUTHOR]

A tetraphenylethylene-containing bisphenol monomer 5-[4-(triphenylvinyl)phenyl]benzene-1,3-diol (TPE-OH) was designed and synthesized by Suzuki coupling and nucleophilic substitution reaction. By adjusting the proportion of TPE-OH, a series of rigid polyaryl ether, namely PPTES, were facilely synthesized by homopolymerization or copolymerization with 4-(4-hydroxyphenyl)-2,3-diazepine-1-one (DHPZ) and 4,40-difluorodiphenyl sulfone (DFS). The following characterization of their structures with nuclear magnetic resonance and infrared spectroscopy confirmed successful synthesis of both monomers and polymers. Large, volume-twisted and non-coplanar rigid tetraphenylethylene could effectively increase the molecular chain spacing and reduce the regularity of the molecular chain, as evidenced by molecular dynamics simulation with Materials Studio, in turn to form an amorphous nature of PPTES phase state. In addition, such PPTESs have excellent solubility, heat resistance, and other comprehensive properties. Their glass transition temperature (Tg) is between 219 and 300°C, and the 5% thermogravimetric temperature of PPTESs locates at 490-539°C under N2 atmosphere. At 1 GHz, the intrinsic dielectric permittivity of polymer films is between 2.32 and 2.61, gradually decreases with TPE-OH content. This work would provide new idea and choice for the selection of polyaryl ether resin bisphenol monomer, and promote the development and application of low-dielectric polyarylether materials. [ABSTRACT FROM AUTHOR]

The development of new π‐conjugated molecular structures with controlled self‐assembly and distinct photophysical properties is crucial for advancing applications in optoelectronics and biomaterials. This study introduces the synthesis and detailed self‐assembly analysis of tetraphenylethylene (TPE) functionalized naphthalene diimide (NDI), a novel donor‐acceptor molecular structure referred to as TPE‐NDI. The investigation specifically focuses on elucidating the self‐assembly behavior of TPE‐NDI in mixed solvents of varying polarities, namely chloroform: methylcyclohexane (CHCl3: MCH) and chloroform: methanol (CHCl3: MeOH). Employing a several analytical methodologies, including UV‐Vis absorption and fluorescence emission spectroscopy, scanning electron microscopy (SEM), X‐ray diffraction (XRD), and dynamic light scattering (DLS), these self‐assembled systems have been comprehensively examined. The results reveal that TPE‐NDI manifests as distinct particles in CHCl3: MCH (fMCH=90 %), while transitioning to flower‐like assemblies in CHCl3: MeOH (fMeOH=90 %). This finding underscores the critical role of solvent polarity in dictating the morphological characteristics of TPE‐NDI self‐assembled aggregates. Furthermore, the study proposes a molecular packing mechanism, based on SEM data, offering significant insights into the design and development of functional supramolecular systems. Such advancements in understanding the molecular self‐assembly new π‐conjugated molecular structures are anticipated to pave the way for novel applications in material science and nanotechnology. [ABSTRACT FROM AUTHOR]

Topological descriptors have drawn more interest recently because of the simplicity of generation and quick evaluation times, by avoiding time-consuming laboratory experiments. The distance based descriptors stand out as being pivotal in the QSAR and QSPR analysis of physico-chemical aspects. Dendrimers are branching polymeric molecules distinguished by its systematic growth pattern. Non-conjugated Ethylene oxide dendritic core attached with tetraphenylethylene is one such hyper branched polymer with strong solubility in a majority of organic solvents making them an active constituent for a variety of experimental purposes. No significant amount of research has been carried over based on the topological aspects of this dendrimer. This study effectively establishes the correlation between the chemical and physical attributes of the structure which can further aid in experimental research. In this work, various fundamental distance based descriptors of Ethylene oxide cored dendrimer have been evaluated by converting the original graph to quotient graphs using Djokovic̀-Winkler relation. Moreover, a graphical comparison of these descriptors has also been plotted to help comprehend the growth trend of these numerical values. [ABSTRACT FROM AUTHOR]

In this work, we functionalized hydroxypropyl cellulose (HPC) by attaching tetraphenylethylene (TPE) via copper‐catalyzed azide‐alkyne cycloaddition (CuAAC). The obtained HPC‐TPE samples displayed water‐solubility, biocompatibility, fluorescence and thermoresponsive properties. The degree of substitution (DSTPE) of HPC‐TPE1 ~ 4 was determined to be 0.002, 0.006, 0.025, and 0.053, respectively. HPC‐TPE could self‐assemble into micelles in water with the hydrodynamic radius (Rh) ranging from 164 to 190 nm. Under different DSTPE, HPC‐TPE samples showed different lower critical solution temperature (LCST) behaviors in light transmittance, Rh and fluorescence. The critical transition temperatures in light transmittance for HPC‐TPE1 ~ 4 solutions were 55–49 °C during the heating process, and were 44–40 °C during the cooling process, respectively. Moreover, HPC‐TPE demonstrated a rapid and sensitive response to Fe3+ with ignoring interferences in the presence of other common metal ions, and could also be used to image 4T1 cells. Therefore, this work offered a general approach for the synthesis of functionalized polymers with promising applications in sensing and bioimaging. [ABSTRACT FROM AUTHOR]

Aromatic heterocyclic compounds have received a lot of interest due to their various important medicinal and biological applications. The broad synthetic investigation and functional usefulness of heterocyclic molecules is driving a surge in research interest. They are found in more than 90% of innovative medications and bridge the gap between biology and chemistry, where so much scientific discovery and application happens. Heterocycles are also useful in a variety of domains, including pharmaceutical chemistry, biochemistry, and others. In this article, quantitative structure‐property relationship (QSPR) models is developed using sombor indices to predict fluorescence properties of aromatic hetero‐cyclic species based on their structural features. This allows researchers to estimate the fluorescence behavior of new molecules without performing experimental measurements. As an application, we have computed the sombor indices for self‐assembled supramolecular graphs made of terpyridine (TPE) and tetraphenylethylene (TPY) molecules that are produced as rosette cycles. This form of rosettes graph is used in electrical sensors, light emitting diodes, bioimaging and photoelectric devices, and so on. Tetraphenylethylene can be used to make fluorescent probes for next‐generation sensing applications with typical induced aggregative emission behavior. [ABSTRACT FROM AUTHOR]

By synergistically employing four key strategies: (I) introducing tetraphenylethylene groups as the central core unit with aggregation‐induced emission (AIE) properties, (II) optimizing the π‐conjugated length by extending the building block branches, (III) incorporating flexible groups containing ethylenic bonds, and (IV) applying crystal engineering to attain dense stacking mode and highly twisty conformation, we successfully synthesized a series of hydrogen‐bonded organic frameworks (HOFs) exhibiting exceptional one/two‐photon excited fluorescence. Notably, when utilizing the fluorescently superior building block L2, HOF‐LIFM‐7 and HOF‐LIFM‐8 exhibiting high quantum yields (QY) of 82.1 % and 77.1 %, and ultrahigh two‐photon absorption (TPA) cross‐sections of 148959.5 GM and 123901.1 GM were achieved. These materials were successfully employed in one and two‐photon excited lysosome‐targeting cellular imaging. It is believed that this strategy, combining building block optimization and crystal engineering, holds significant potential for guiding the development of outstanding fluorescent HOF materials. [ABSTRACT FROM AUTHOR]

The interaction between organic photoelectric molecules leads to the formation of a certain aggregation structure, which plays a pivotal role in the charge transport at the intermolecular interface. In view of this, we investigated the mechanism and law of intermolecular interaction by detecting the self-assembled behaviors between organic photoelectric molecules at the interface by scanning tunneling microscopy (STM). In this work, the structural transformations of tetraphenylethylene acids (H4ETTCs) on graphite surface induced by temperature and triazine derivatives (zcy-19, zcy-27, and zcy-38 molecules) were studied by STM technology and density functional theory (DFT) calculations. At room temperature, zcy-19 and H4ETTC molecules formed a small range of ordered co-assembled nanostructure, while for zcy-27 or zcy-38 molecules, no co-assembled nanostructures were observed and only their own self-assembled structures existed on graphite surface, individually. In the thermal annealing trials, the original co-assembled H4ETTC/zcy-19 structure disappeared, and only zcy-19 and H4ETTC self-assembled in separate domains. Nevertheless, new well-ordered H4ETTC/zcy-27 or H4ETTC/zcy-38 co-assembled structures appeared at different annealing temperatures, respectively. Combined with DFT calculations, we further analyzed the mechanism of such structural transformations by triazine derivatives and temperature. Results reveal that triazine derivatives could interact with H4ETTC by N-H...O and O-H...N hydrogen bondings, and whether temperature or zcy series compounds could achieve successful regulation of H4ETTC assembly behavior is closely associated with the conjugated skeleton length of zcy series compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] 'Ligand-free' Pd-catalyzed reaction between arylboronic acid and diphenylacetylene affords a set of polyphenylated olefins and 1,2,3,4-tetraphenylnaphthalene whose yields are dependent on counteranion of PdII salt and additive nature. Tetraphenylethylene and hexaphenylbuta-1,3-diene are likely formed in tandem arylation/cross-coupling reaction with the participation of hydroxo/alkoxo alkenyl Pd species, whereas 1,2,3,4-tetraphenylnaphthalene formation probably proceeds through tandem arylation/C–H activation by halide-containing alkenyl Pd complexes. [ABSTRACT FROM AUTHOR]

The precisely modulated synthesis of programmable light‐emitting materials remains a challenge. To address this challenge, we construct four tetraphenylethylene‐based supramolecular architectures (SA, SB, SC, and SD), revealing that they exhibit higher electrochemiluminescence (ECL) intensities and efficiencies than the tetraphenylethylene monomer and can be classified as highly efficient and precisely modulated intramolecular aggregation–induced electrochemiluminescence (PI‐AIECL) systems. The best‐performing system (SD) shows a high ECL cathodic efficiency exceeding that of the benchmark tris(2,2′‐bipyridyl)ruthenium(II) chloride in aqueous solution by nearly six‐fold. The electrochemical characterization of these architectures in an organic solvent provides deeper mechanistic insights, revealing that SD features the lowest electrochemical band gap. Density functional theory calculations indicate that the band gap of the guest ligand in the SD structure is the smallest and most closely matched to that of the host scaffold. Finally, the SD system is used to realize ECL‐based cysteine detection (detection limit=14.4 nM) in real samples. Thus, this study not only provides a precisely modulated supramolecular strategy allowing chromophores to be controllably regulated on a molecular scale, but also inspires the programmable synthesis of high‐performance aggregation‐induced electrochemiluminescence emitters. [ABSTRACT FROM AUTHOR]

This study reports the synthesis of cofacial organic cage molecules containing aggregation‐induced emissive (AIE) luminogens (AIEgens) through four‐fold Cu(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) "click" reactions. The shorter AIEgen, tetraphenylethylene (TPE), afforded two orientational isomers (TPE‐CC‐1A and TPE‐CC‐1B). The longer AIEgen, tetrabiphenylethylene (TBPE), afforded a single isomer (TBPE‐CC‐2). The click reaction employed is irreversible, yet it yielded remarkable four‐fold click products above 40 %. The phenyl rings around the ethylene core generate propeller‐shaped chirality owing to their orientation, which influences the chirality of the resulting cages. The shorter cages are a mixture of PP/MM isomers, while the longer ones are a mixture of PM/MP isomers, as evidenced by their x‐ray structures. The newly synthesized cage molecules are emissive even in dilute solutions (THF) and exhibit enhanced AIE upon the addition of water. The aggregated cage molecules in aqueous solution exhibit turn‐off emission sensing of nitroaromatic explosives, with selectivity to picric acid in the 25–38 nanomolar detection range. [ABSTRACT FROM AUTHOR]

Multicomponent metallacages can integrate the functions of their different building blocks to achieve synergetic effects for advanced applications. Herein, based on metal‐coordination‐driven self‐assembly, we report the preparation of a series of isoreticular tetraphenylethylene‐based metallacages, which are well characterized by multinuclear NMR, ESI‐TOF‐MS and single‐crystal X‐ray diffraction techniques. The suitable integration of photosensitizing tetraphenylethylene units as faces and Re catalytic complexes as the pillars into a single metallacage offers a high photocatalytic hydrogen production rate of 1707 μmol g−1 h−1, which is one of the highest values among reported metallacages. Femtosecond transient absorption and DFT calculations reveal that the metallacage can serve as a platform for the precise and organized arrangement of the two building blocks, enabling efficient and directional electron transfer for highly efficient photocatalytic performance. This study provides a general strategy to integrate multifunctional ligands into a certain metallacage to improve the efficiency of photocatalytic hydrogen production, which will guide the future design of metallacages towards photocatalysis. [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]

Fluorescent hydrogels with fast and reversible responses have attracted extensive attention, and it remains a challenge to design multistimuli-responsive fluorescent hydrogel through a facile and versatile method. Meanwhile, the segmental motion in hydrogels is of significance for the various functions of hydrogels such as chemical reactivity, self-healing, and mechanical strength, etc., however, it is difficult and complicated to in situ investigate the segmental motion under different conditions. In this work, a multistimuli-responsive fluorescent hydrogel was designed and fabricated by introducing a tetraphenylethylene (TPE) derivative as a nonaggregated crosslinker in the gel network. Since the intermolecular rotation of TPE at the crosslinking point was directly integrated with the dynamic conformational transition of the macromolecular network, the mobility of macromolecular segments can be monitored by the fluorescence intensity of the hydrogel. The prepared hydrogel has promising fluorescence responses to temperature, pH, metal ions, and hydrogen bonding agents, and characterization of the fluorescence and the chain segmental motion showed that the weaker the mobility of the network macromolecular chain is, the stronger the fluorescence intensity is. Furthermore, due to the multistimuli-responsive fluorescence of the hydrogel, such fluorescent hydrogels can be designed as reversible patterning displays and biomimetic color/shape adjustable actuators, with various potential applications. [ABSTRACT FROM AUTHOR]

Many aggregation‐induced emission (AIE) molecules based on tetraphenylethylene (TPE) structure have been synthesized, but a clear understanding of the photophysical difference between different isomeric pyridyl‐based tetraphenylethylene molecules remains elusive. Herein, we designed a series of isomeric tetraphenylethylene‐pyridines (o‐Py‐TPE, m‐Py‐TPE, p‐Py‐TPE) to investigate the influence of the position of N atoms in the pyridine subunit on the photophysical property of the whole molecule by detailed DFT calculations and single‐crystal structures analysis. All compounds show typical AIE properties, and notably, the meta pyridyl isomer (m‐Py‐TPE) shows the highest solid photoluminescence quantum yield (PLQY) up to 64.56 %. Further investigation and DFT calculations indicate that the center C=C bond dihedral angles of the TPE subunit in the solid state of these compounds, which are affected by C−H⋅⋅⋅π interaction, play a vital role in their emission and PLQY properties. This work provides underlying principles for the design of pyridyl‐based TPE molecules with high photoluminescent performance in the future. [ABSTRACT FROM AUTHOR]

Fabrication of fluorescent cellulose with aggregation‐induced emission (AIE) characteristics is usually achieved by grafting tetraphenylethylene (TPE) to the cellulose backbone using TPE derivatives with highly active functional groups such as carboxylic, isothiocyanate, and alkynyl groups. However, besides the complicated synthetic routes of these TPE derivatives, conversion of hydroxyl groups in the cellulose chain to more reactive groups such as amine or azide groups is usually involved, and the resulting products have a degree of substitution (DS) of TPE lower than 0.08. Herein, a facile one‐pot strategy for the grafting of a TPE group to the cellulose backbone with high DS of up to 0.22 in a CO2 switchable solvent under mild reaction conditions is reported. The hydroxyl groups in the cellulose are in situ converted to cellulose carbonate intermediately during the dissolution step. Subsequently, nucleophilic substitution between the intermediate and a halogenated TPE derivative with bromine atom as leaving group is carried out to achieve the effective grafting of TPE. The synthetic route for this promising TPE derivative is much more convenient than those of TPE derivatives reported in previous studies. This work suggests a new and facile pathway for the synthesis of high‐emission fluorescent cellulose with AIE functionality. [ABSTRACT FROM AUTHOR]

Highly-efficient molecular photoswitching occurs ex-situ but not to-date inside electronic devices due to quenching of excited states by background interactions. Here we achieve fully reversible in-situ mechano-optoelectronic switching in self-assembled monolayers (SAMs) of tetraphenylethylene molecules by bending their supporting electrodes to maximize aggregation-induced emission (AIE). We obtain stable, reversible switching across >1600 on/off cycles with large on/off ratio of (3.8 ± 0.1) × 103 and 140 ± 10 ms switching time which is 10-100× faster than other approaches. Multimodal characterization shows mechanically-controlled emission with UV-light enhancing the Coulomb interaction between the electrons and holes resulting in giant enhancement of molecular conductance. The best mechano-optoelectronic switching occurs in the most concave architecture that reduces ambient single-molecule conformational entropy creating artificially-tightened supramolecular assemblies. The performance can be further improved to achieve ultra-high switching ratio on the order of 105 using tetraphenylethylene derivatives with more AIE-active sites. Our results promise new applications from optimized interplay between mechanical force and optics in soft electronics. To date the performance of molecular electronics compared to silicon limits their applications. Yang et al. develop the first mechano-optoelectronic switch based on mechanically controlled aggregation-induced emission of the self-assembled molecules, which can be reversibly switched at high speed. [ABSTRACT FROM AUTHOR]

Tetraphenylethylene (TPE)-based ligands are appealing for constructing metal-organic frameworks (MOFs) with new functions and responsiveness. Here, we report a non-interpenetrated TPE-based scu Zr-MOF with anisotropic flexibility, that is, Zr-TCPE (H4TCPE = 1,1,2,2-tetra(4-carboxylphenyl)ethylene), remaining two anisotropic pockets. The framework flexibility is further anisotropically rigidified by installing linkers individually at specific pockets. By individually installing dicarboxylic acid L1 or L2 at pocket A or B, the framework flexibility along the b-axis or c-axis is rigidified, and the intermolecular or intramolecular motions of organic ligands are restricted, respectively. Synergistically, with dual linker installation, the flexibility is completely rigidified with the restriction of ligand motion, resulting in MOFs with enhanced stability and improved separation ability. Furthermore, in situ observation of the flipping of the phenyl ring and its rigidification process is made by 2H solid-state NMR. The anisotropic rigidification of flexibility in scu Zr-MOFs guides the directional control of ligand motion for designing stimuli-responsive emitting or efficient separation materials. Metal-organic frameworks (MOFs) with adjustable porosity and tunable functionality have attracted considerable attention, but the directional control of intermolecular and intramolecular motion of TPE-based ligands in the non-interpenetrated flexible MOFs has not yet been studied. Here, the authors report a non-interpenetrated tetraphenylethylene-based MOF with anisotropic flexibility. [ABSTRACT FROM AUTHOR]

We synthesized a new tetraphenylethylene-modified chitosan bioconjugate, CS-TPE, that shows the aggregation-induced emission effect. It can self-assemble into fluorescent polymeric nanoparticles in an aqueous solution at pH 5.3 either alone or with the water-soluble bowl-shaped six-fold carboxylated tribenzotriquinacene derivative TBTQ-C6 via host–guest binding. The spherical nanoparticles formed by CS-TPE amphiphiles or TBTQ-C6/CS-TPE supra-amphiphiles disintegrated under alkaline stimulation at pH 10.4 and the dispersion of the aggregates after the collapse in the presence of TBTQ-C6 was greatly improved. In addition, the fluorescence of CS-TPE was significantly enhanced by introducing TBTQ-C6, and remained relatively stable with variations in pH for both CS-TPE and TBTQ-C6/CS-TPE. Such pH-responsive supramolecular spherical nanoparticles with stable fluorescence emission based on CS-TPE or TBTQ-C6/CS-TPE may find applications in various fields, including the development of visual oral drug delivery systems.

The development of novel organic fluorescent materials with strong luminescence in the aggregate state as well as stimuli response under external forces is of great importance for practical applications in the solid state. It is established that triphenylethylene and tetraphenylethylene are propeller-type aromatic molecular structures present in the majority of organic emitters with aggregation-induced emission (AIE) properties to prevent aggregation-caused quenching (ACQ). In this study, we have incorporated a spiro-xanthene (SFX) core for the first time to design a new donor–π–acceptor–π–donor 4,4′-((3′,6′-dibutoxyspiro[fluorene-9,9′-xanthene]-2,7-diyl)bis(thiophene-5,2-diyl))bis(N,N-diphenylaniline) (SP-TH) luminescent material with aggregation induced emission (AIE) and mechano-responsive properties. DFT calculations were carried out to study the electronic properties of SP-TH. The photophysical and electrochemical properties of SP-TH were systematically investigated. The photophysical (UV-Vis and PL spectroscopies) studies indicate that SP-TH has AIE features. In addition, the mechano-stimuli response of SP-TH was also investigated, and a hypsochromic shift (yellowish green to bluish green) was observed upon grinding the SP-TH sample and was analyzed using PXRD. [ABSTRACT FROM AUTHOR]

Two iron(II) compounds with the general formula of [Fe(phen‐TPE)2(NCX)2] ⋅ Y (phen‐TPE=3‐(tetraphenylethylene)‐1,10‐phenanthroline; X=S and Y=2DMF for 1 ⋅ 2DMF; X=Se and Y=DMF for 2 ⋅ DMF) were synthesized and characterized by single‐crystal X‐ray crystallography and magnetic measurements. Both compounds exhibited thermal‐induced complete one‐step spin‐crossover (SCO) behavior with the critical transition temperatures of 210 K and 260 K for 1 ⋅ 2DMF and 2 ⋅ DMF, respectively. The SCO behavior of these two isomorphic compounds depended significantly on robust intermolecular π⋅⋅⋅π interactions, NCX− groups and solvent molecules. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD), an amyloid-related disease, seriously endangers the health of elderly individuals. According to current research, its main pathogenic factor is the amyloid protein, which is a kind of fibrillar aggregate formed by noncovalent self-assembly of proteins. Based on the characteristics of aggregation-induced emission (AIE), a bislactosyl-decorated tetraphenylethylene (TPE) molecule TMNL (TPE + malononitrile + lactose), bearing two malononitrile substituents, was designed and synthesized in this work. The amphiphilic TMNL could self-assemble into fluorescent organic nanoparticles (FONs) with near-infrared (NIR) fluorescence emission in physiological PBS (phosphate buffered saline), achieving excellent fluorescent enhancement (47-fold) upon its combination with Aβ1–42 fibrils. TMNL was successfully applied to image Aβ1–42 plaques in the brain tissue of AD transgenic mice, and due to the AIE properties of TMNL, no additional rinsing process was necessary. It is believed that the probe reported in this work should be useful for the sensitive detection and accurate localization mapping of Aβ1–42 aggregates related to Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) have found use in broad range of applications such as in catalysis and nanomedicine. Despite the fact that thiol-based AuNPs have been widely studied, they suffer from relative instability in various conditions, such as high and low temperatures, pH variations, and are prone to oxidation. Over the last decade, N-heterocyclic carbenes (NHCs) have been under spotlight as suitable ligands to stabilize metal nanoparticles and surfaces. Although NHC-functionalized AuNPs have been shown to outperform their thiol-based analogs in terms of stability, their applications in nanomedicine have not been realized. Hybrid nanomaterials, such as AuNPs tagged with π-conjugated molecules with aggregation-induced emission (AIE) property, are promising candidates to develop fluorescent materials for cellular imaging. The combination of NHC-stabilized AuNPs with AIE to form stable, fluorescent hybrid AuNPs is of significant interest to open the door to develop new NHC-based nanomaterials. Herein, we report the synthesis and characterization of water-soluble fluorescent NHC-decorated AuNPs for potential applications in nanomedicine. Their stability in biologically relevant conditions is investigated. [ABSTRACT FROM AUTHOR]

We report the unique synthesis of chiral supramolecular tri‐ and penta‐BCPs with controllable chirality using kinetically adjusted seeded supramolecular copolymerization in THF and DMSO (99 : 1, v/v). Tetraphenylethylene (d‐ and l‐TPE) derivatives bearing d‐ and l‐alanine side chains formed thermodynamically favored chiral products via a kinetically trapped in monomeric state with a long lag phase. In contrast, achiral TPE‐G containing glycine moieties did not form a supramolecular polymer owing to the energy barrier in its kinetically trapped state. We show that the copolymerization of the metastable states of TPE‐G not only enables the generation of supramolecular BCPs by the seeded living growth method, but also transfers chirality at the seed ends. This research demonstrates the generation of chiral supramolecular tri‐ and penta‐BCPs with B‐A‐B, A‐B‐A‐B‐A, and C‐B‐A‐B‐C block patterns accompanying chirality transfer via seeded living polymerization. [ABSTRACT FROM AUTHOR]

High refractive index polymers (HRIPs) have drawn attention for their optoelectronic applications and HRIPs with excellent transparency and facile preparation are highly demanded. Herein, sulfur-containing all organic HRIPs with refractive indices up to 1.8433 at 589 nm and excellent optical transparency even in one hundred micrometre scale in the visual and RI region as well as high weight-average molecular weights (up to 44500) are prepared by our developed organobase catalyzed polymerization of bromoalkynes and dithiophenols in yields up to 92%. Notably, the fabricated optical transmission waveguides using the resultant HRIP with the highest refractive index display a reduced propagation loss compared with that generated by the commercial material of SU-8. In addition, the tetraphenylethylene containing polymer not only exhibits a reduced propagation loss, but also is used to examine the uniformity and continuity of optical waveguides with naked eyes because of its aggregation-induced emission feature. The easy preparation of high efractive index transparent polymers is highly desirable owing to their interesting optoelectronic applications. Here, the authors apply an organobase catalyzed polymerization of bromoalkynes and dithiophenols to produce sulfur-containing all organic high refractive index polymers with excellent optical transparency. [ABSTRACT FROM AUTHOR]

This study presents the synthesis and characterization of novel azido molecules with demonstrated crosslinking ability when used as additives in polymer/fullerene organic solar cells. These compounds derived from fullerenes C60 and C70, or dyes from perylenediimide, perylene and tetraphenylethylene frameworks, bearing a different number of azido groups, are of particular interest to stabilize and increase the thermal stability of the device morphology. In particular, the electro and photoactive dye derivatives allow the introduction of additional functionality with the possibility of extending the absorption domain of the photoactive layer. In addition, and more broadly, such azido crosslinkers could find applications in the field of optoelectronic devices as a simple and cheap strategy to improve the performance and long‐term stability of organic solar cells, perovskites solar cells, or organic light‐emitting diodes. [ABSTRACT FROM AUTHOR]

Herein we report the self-assembly of an amino-acid substituted tetraphenylethylene (TPE) into a hydrogen-bonded dimeric capsule. Depending on the conditions applied the presented TPE derivative exhibits bluish photoluminescence with QYs up to 24% due to the AIE effect and excimer formation. [ABSTRACT FROM AUTHOR]

A fluorescent polymer probe was developed by connecting tetraphenylethylene (TPE) with glucose via the formation of borate ester linkages. Based on the selective breaking of C–B bonds, the macroscopic and fluorescence detection of reactive oxygen species (ROS) in vitro and in cells was successfully realized. [ABSTRACT FROM AUTHOR]

Dual‐state emission luminogens (DSEgens) are receiving research interest in the construction of multifunctional materials due to their inherent advantage of high emission efficiency in both the molecularly dispersed solution state and the solid state. However, it remains challenging in synthesizing DSEgens via a delicate manipulation of the molecular structures. This work presents an example of bright DSEgen synthesis by tuning the molecular electronic structures and conformations. Three coumarin‐tetraphenylethylene (TPE) molecules with a donor‐acceptor electronic structure and highly twisting conformations have been synthesized. While compound resulting from direct conjugation of coumarin with a TPE unit shows aggregation‐induced emission, compound with an N,N‐diaminoethyl modification on the 7‐position of coumarin and compound with a further phenyl linker between coumarin and TPE units feature strong dual‐state emission. Benefiting from their strong solid emission and twisting conformations, these fluorophores display reversible mechanofluorochromism. Finally, applications for rewritable information storage in the solid state and live‐cell imaging in the solution state were demonstrated. [ABSTRACT FROM AUTHOR]

Through McMurry coupling reaction, three meso‐position functionalized pillar[5]arene derivatives (H‐1, H‐2, and H‐3) have been successfully prepared by embedding aggregation‐induced emission luminogens (AIEgens, diphenyldibenzofulvene (DPDBF) and tetraphenylethylene (TPE)) into the skeleton of supramolecular macrocycles. H‐1, bearing [15]paracyclophane ([15]PCP) and DPDBF moiety, exhibits yellow emission and demonstrates obvious AIE effect. In order to further improve the host‐guest properties of this type of structure, H‐2 and H‐3 are prepared by replacing the [15]PCP moiety with pillar[5]arene backbone, both of which show significant AIE effect and excellent host‐guest complexation properties with pyrazine salt guest G‐1 and 1,4‐dicyanobutane G‐2. Our findings indicate that G‐1 can decrease the fluorescence intensity of the AIE macrocycles, while G‐2 can increase their fluorescence intensity in solution. [ABSTRACT FROM AUTHOR]

We report a novel stimuli‐responsive fluorescent material platform that relies on an evocation of aggregation‐induced emission (AIE) from tetraphenylethylene (TPE)‐based surfactants localized at one hemisphere of biphasic micro‐scale Janus emulsion droplets. Dynamic alterations in the available interfacial area were evoked through surfactant‐induced dynamic changes of the internal droplet morphology that can be modulated as a function of the balance of interfacial tensions of the droplet constituent phases. Thus, by analogy with a Langmuir–Blodgett trough that enables selective concentration of surfactants at a liquid–gas interface, we demonstrate here a method for controllable modulation of the available interfacial area of surfactant‐functionalized liquid–liquid interfaces. We show that a morphology‐dependent alteration of the interfacial area can be used to evoke an optical signal, by selectively assembling synthesized TPE‐based surfactants on the respective droplet interfaces. A trigger‐induced increase in the concentration of TPE‐based surfactants at the liquid–liquid interfaces results in an evocation of aggregation‐induced emission (AIE), inducing an up to 3.9‐fold increase in the measured emission intensity of the droplets. [ABSTRACT FROM AUTHOR]

A dimeric fluorescent macrocycle m‐TPE Di‐EtP5 (meso‐tetraphenylethylene dimeric ethoxypillar[5]arene) is synthesized based on the meso‐functionalized ethoxy pillar[5]arene. Through the connectivity of two pillar[5]arenes by CC double bond, the central tetraphenylethylene (TPE) moiety is simultaneously formed. The resultant bicyclic molecule not only retains the host–guest properties of pillararenes but also introduces the interesting aggregation‐induced emission properties inherent in the embedded TPE structure. Three dinitrile derivatives with various linkers are designed as guests (G1, G2, and G3) to form host–guest assemblies with m‐TPE Di‐EtP5. The morphological control and fluorescence properties of the assemblies are successfully realized. G1 with a shorter alkyl chain as the linker completely threads into the cavities of the host. G2, due to its longer chain length, forms a linear supramolecular polymer upon binding to m‐TPE Di‐EtP5. G3 differs from G2 by possessing a bulky phenyl group in the middle of the chain, which can be further assembled with m‐TPE Di‐EtP5 to form supramolecular layered polymer and precipitated out in solution, and can be efficiently applied to photocatalytic reactions. [ABSTRACT FROM AUTHOR]

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Herein, trimethyl‐β‐cyclodextrin (TMe‐β‐CDx) and γ‐cyclodextrin (γ‐CDx) could dissolve a tetraphenylethylene derivative (TPE−OH4) in water through high‐speed vibration milling. The fluorescence intensity of the TMe‐β‐CDx−TPE−OH4 complex was much higher than that of the γ‐CDx−TPE−OH4 complex, as the rotation of the central C=C double bond of TPE−OH4 after photoactivation was inhibited in a smaller TMe‐β‐CDx cavity in comparison with the γ‐CDx cavity. In contrast, the fluorescence intensity of the γ‐CDx−TPE−OH4 complex was very weak; nevertheless, it increased after the addition of liposomes due to the transfer of TPE−OH4 from the γ‐CDx cavity to the lipid membrane as a "turn‐on" phenomenon. Furthermore, to apply temperature sensor, it was demonstrated that the fluorescence intensity in the liposomes depended on the phase‐transition temperature. By using the fluorescence turn‐on phenomenon, TPE−OH4 could detect the presence of HeLa cells and E. coli by fluorescence. [ABSTRACT FROM AUTHOR]