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We report a unique category of π‐extended diaza[7]helicenes with double negative curvatures. This is achieved by two‐fold regioselective heptagonal cyclization of the oligoarylene‐carbazole precursors through either intramolecular C−H arylation or Scholl reaction. The fusion of two heptagonal rings in the helical skeleton dramatically increases the intramolecular strain and forces the two terminal carbazole moieties to stack in a compressed fashion. The presence of the deformable negatively curved heptagonal rings endows the resulting diaza[7]helicenes with dynamic chiral skeletons, aggregation‐induced emission feature and relatively low racemization barrier of ca. 25.6 kcal mol−1. Further π‐extension on the carbazole moieties subsequently leads to a more sophisticated C2‐symmetric homochiral triple helicene. Notably, these π‐extended diaza[7]helicenes show structure‐dependent stacking upon crystallization, switching from heterochiral packing to intra‐layer homochiral stacking. Interestingly, the C2‐symmetric triple helicene molecules spontaneously resolve into a homochiral lamellar structure with 31 helix symmetry. Upon ultrasonication in a nonsolvent, the crystals can be readily exfoliated into large‐area ultrathin nanosheets with height of ca. 4.4 nm corresponding to two layers of stacked triple helicene molecules and relatively thicker nanosheets constituted by even‐numbered molecular lamellae. Moreover, regular hexagonal thin platelets with size larger than 30 μm can be readily fabricated by flash aggregation. [ABSTRACT FROM AUTHOR]

Nanostructured conjugated polymers are of widespread interest due to their broad applications in organic optoelectronic devices, biomedical sensors and other fields. However, the alignment of conjugated nanostructures perpendicular to a surface remains a critical challenge. Herein, we report a facile method to directly self‐assemble a poly(3‐(2‐ethylhexyl)thiophene), P3EHT‐based block copolymer into densely aligned micellar brushes through surface‐initiated living crystallization‐driven self‐assembly. The presence of an ethyl pendant on the side group intrinsically moderates the crystallization rate of the polythiophene main chains, and hence favors the controlled living growth of long conjugated fibers and the subsequent fabrication of conjugated micellar brushes. The corona of the micellar brush can be further decorated with platinum nanoparticles, which enables the formation of erect nanoarrays with heights up to 2700 nm in the dried state. This also renders the micellar brush catalytically active toward hydrogen evolution reaction, which shows a low overpotential of 27 mV at 10 mA cm−2. Notably, the P3EHT‐based micellar brush can simultaneously grow with polyferrocenyldimethylsilane, PFS‐based micellar brush on the same surface without any significant interference between the two systems. Thus, these two micellar brushes can be patterned through site‐selective immobilization of two types of seeds followed by independent living self‐assembly. [ABSTRACT FROM AUTHOR]

Enantiopure helicenes have been extensively investigated due to their outstanding chiroptical properties, while helicene racemates are considered as chiroptically silent. Here, we describe a facile method to produce circularly polarized luminescence (CPL) from helicene racemates via supramolecular association with DNA in aqueous solution. Racemic cationic helicene derivatives are immobilized in the grooves of commercially available double‐stranded right‐handed DNA, and the discrimination of left‐ and right‐handed helicenes by chiral DNA is monitored by single molecule force spectroscopy. This subsequently leads to the generation of prominent CPL with dissymmetric factor |glum| of close to 0.01, which is approximate to enantiopure helicenes. The strategy developed in this work avoids the tedious and expensive chiral resolution process and provides a distinctive insight into the fabrication of CPL‐emitting systems. [ABSTRACT FROM AUTHOR]

The rapid development of continuous flow processes is driving innovations in various chemical syntheses and industrial productions. Immobilizing catalysts in flow reactors allows transformations with high‐efficiency and excludes the subsequent separation procedures. This concept outlines the approaches to incorporate catalysts within flow reactors, with particular focus on the application of additional supports including inorganic materials like silica, zeolite and reduced graphene oxide, polymeric materials like polymer packings, monoliths, cross‐linked gels and polymer brushes, and other materials for specific conditions like transparent glass fibers and glass beads. Furthermore, advanced methods to develop ordered micro‐/nanoarrays from internal walls of flow channels for immobilization of catalysts as well as application of innovative vortex fluidic devices are discussed to inspire new designs of supports for novel fluidic reactors with broad applications. [ABSTRACT FROM AUTHOR]

Synthetic innovation for constructing sophisticated nanographenes is of fundamental significance for a variety of advanced applications. Herein, we report a distinctive method to prepare π‐extended chiral nanographenes with 29 benzenoid rings and two helical breaches from a highly crowded perylene‐cored oligoarylene precursor. Under Scholl's conditions, the reaction predominantly involves the regioselective and sequential cyclization in the peri‐ and bay regions of the perylene core, and the complanation of the 1‐phenyl[5]helicene intermediate module via 1,2‐phenyl migration. The resulting chiral nanographenes are configurationally stable at 180 °C due to the high diastereomerization barriers of ca. 45 kcal mol−1. These molecules also possess globally delocalized π‐systems with low HOMO/LUMO gaps, leading to nearly panchromatic absorption, intensive electronic circular dichroism signals and deep‐red circularly polarized luminescence. [ABSTRACT FROM AUTHOR]

Ultralong room‐temperature phosphorescence (RTP) is highly useful for information encryption, organic electronics, bioelectronics, etc. However, the preparation of related metal‐free materials with multiple colors across the full spectrum remains a major challenge. Herein, a facile method is developed to fabricate boron‐doped carbon dot (B‐CD) composites with full‐color long lifetime RTP continuously tailorable in the range of 466–638 nm simply by pyrolysis of the citric acid and boric acid precursors with various mass ratios at different temperatures. This leads to the formation of luminescent B‐CD centers in a rigid polycrystalline B2O3 matrix, which effectively stabilizes the triplet excited states of B‐CDs. Thus, the composites become phosphorescent over a relatively long period (5–12 s) after the removal of the irradiation source. Meanwhile, the increased particle size and oxidation degree of B‐CDs obtained at larger citric acid feeding or higher pyrolysis temperature continuously shift the phosphorescence from blue to red. Due to the formation of multiple luminescence centers, the RTP can also be finely modulated by the excitation wavelength. The resulting B‐CD composites with highly tunable long lifetime RTP further allow a variety of distinctive applications in multidimensional encryption handily utilizing space, time, and color variations. [ABSTRACT FROM AUTHOR]

Flow reactors are appealing alternatives to conventional batch reactors for heterogeneous catalysis. However, it remains a key challenge to firmly immobilize the catalysts in a facile and flexible manner and to simultaneously maintain a high catalytic efficiency and throughput. Herein, we introduce a dense cylindrical micelle brush support in glass capillary flow reactors through a living crystallization‐driven self‐assembly process initiated by pre‐immobilized short micelle seeds. The active hairy corona of these micellar brushes allows the flexible decoration of a diverse array of nanocatalysts, either through a direct capture process or an in situ growth method. The resulting flow reactors reveal excellent catalytic efficiency for a broad range of frequently utilized transformations, including organic reductions, Suzuki couplings, photolytic degradations, and multistep cascade reactions, and the system was both recyclable and durable. Significantly, this approach is readily applicable to long capillaries, which enables the construction of flow reactors with remarkably higher throughput. [ABSTRACT FROM AUTHOR]

Immune and targeted therapy are becoming the first‐line treatment for renal cell carcinoma (RCC). However, therapeutic outcomes are limited due to the low efficiency and side effect. Here, it is found that helicenes are able to exhibit an anticancer capability through changing the molecular structure from planar to nonplanar. Furthermore, the cytotoxicity in vitro and cancer inhibition ability of nonplanar helicenes increase with its aromatic rings' number. It is further demonstrated that benzo[4]helicenium shows the specific killing efficiency against the RCC cancer as compared to normal kidney cells. This is majorly originated from a more selective damage of benzo[4]helicenium for mitochondria and DNA in RCC cancer cells, not the normal kidney. The selective killing ability of benzo[4]helicenium makes it have potential to be used as a targeted drug for the precise treatment of RCC. [ABSTRACT FROM AUTHOR]

In the field of plasma diagnosis, the measurement of the distribution function is significant because the distribution function is the basis for the use of plasma kinetic theory and it is the prerequisite for analyzing many physical phenomena, such as Landau damping (wave-particle resonance phenomenon) and ion sheath. Theoretical analysis and a large number of experiments have proved that plasma components do not obey Boltzmann–Gibbs statistics and can be well described by nonextensive statistical mechanics. The field of nonextensive electric probe has also made great progress, and the invention of the nonextensive single electric probes has developed and strengthened the power of plasma diagnostics. The nonextensive electric probe can not only measure the electron nonextensive parameter of plasma that cannot be measured by traditional probes but can also measure more accurate plasma parameters that can also be measured by traditional probes, such as Te, Φp, ne, Φf, and α q F e . However, diagnosing the plasma distribution function by the nonextensive electric probe has not been thoroughly and systematically analyzed and discussed. Here, we show the measurement of the plasma distribution function with a nonextensive single electric probe. This work expands the diagnostic capabilities of the nonextensive single electric probe. We utilize the nonextensive single electric probe theory to analyze the experimental data points of the I–V curve, measure the plasma electron distribution function f v x , and display the distribution curve (figure f-vx), and we also measure the plasma parameters of q F e , Te, Φp, ne, Φf, α q F e , etc. The proposed method provides a new approach to the diagnosis of the plasma distribution function and contributes to a more accurate and comprehensive grasp of plasma, which creates better conditions for us to take advantage of plasma. These initial results illustrate the potential of the nonextensive electric probe in the field of plasma diagnosis and, more generally, in accelerating the progress of fusion-energy science and helping to understand complex physical systems. [ABSTRACT FROM AUTHOR]

Hierarchical self‐assembly of small molecules into supramolecular structures across various length scales is of prominent importance to deeply understand and mimic the biological systems. Here, chiral nanoribbons that assembled from chiral phenylalanine and achiral coumarin derivatives can curve and grow into higher ordered hollow microstructures, which exhibit enhanced acid and alkali resistance. This is predominantly facilitated by the subtle hydrogen bonding interactions and specific steric hindrance between the two molecules. With the addition of metal ions and consequently, the extra association via coordination, these nanoribbons can wrap in a more condensed fashion and eventually form solid microstructures. This study provides implications in understanding the hierarchically biological self‐assembly process and is helpful for the construction of advanced artificial biomedical materials. [ABSTRACT FROM AUTHOR]

Theoretical analysis and a large number of experiments have proved that plasma components do not satisfy Boltzmann–Gibbs statistics and can be well described by nonextensive statistical mechanics, while sheath potential coefficients in plasma with nonextensive distribution are not investigated deeply and comprehensively. Here, we investigate the ion sheath formed around a nonextensive single electric probe in plasma described by nonextensive statistical mechanics, and find that the sheath potential coefficient is related to the electron nonextensive parameter, besides the extensive limit the results return to the case of the Boltzmann–Gibbs statistical framework. The sheath potential coefficient presents different dependences on the electron nonextensive parameters in different regions. We also have calculated the corresponding method error and evaluated with a set of real experiment data, and found that the error is as high as 83.91% indicating that the effect of nonextensive parameters should be considered in the actual measurement. [ABSTRACT FROM AUTHOR]

Abstract: We report the co‐assembly of aromatic donor (D) and acceptor (A) molecules into purple sponge‐like supramolecular gels through susceptible charge transfer interactions with the aid of solvophobic interactions. The gel remained intact with the addition of up to 23 % (v/v) of nonpolar good solvents, such as toluene and xylene, but dissociated in the presence of <2 % (v/v) of polar solvents, such as tetrahydrofuran, ethyl acetate, and alcohols, with highly distinguishable changes of color. Notably, the gel dissolved within 1 min and the solution turned blue when 0.1 % (v/v) of methanol was added. The response to trifluoroacetic acid was extremely sensitive (i.e., the gel vanished immediately in the presence of 2 equivalents of trifluoroacetic acid), and the subsequent addition of trimethylamine could recover the purple gel. The multiple and visible response thus render the D–A gels as a potential detector for sensing complex chemical environments. [ABSTRACT FROM AUTHOR]