Latest ArticlesA pyrene-tiaraed pillar[5]arene derivative was synthesized, which showed a concentration-independent intensive excimer emission. Photolysis of the pyrene-tiaraed pillar[5]arene led to a switch from excimer to monomer emission, applicable to photo-writing.
We report herein a new fluorescent probe for the selective recognition and determination of dodine among 20 different pesticides. This fluorescent probe was assembled through host-guest complexation between cucurbit[10]uril (Q[10]) and aminopropyl-1-pyrenebutanamide (PBA) and is designated as PBA@Q[10]. Addition of dodine to PBA@Q[10] results in a dramatic enhancement of fluorescence intensity at 390 nm, accompanied by fluorescence quenching at 488 nm. On this basis, the detection limit is 6.78×10-7 mol/L. The response mechanism is a competitive interaction: dodine occupies the cavity of Q[10] and forces PBA to leave.
Star shape bridged pillar[5]arene trimer (C3-PLT) based on benzene-1,3,5-tricarboxamide (BTAs) was successfully synthesized, which exhibited outstanding guest responsive morphology transition properties. The morphology tuning studies was efficiently achieved with the addition of competitive guest molecules G1 and G2 by various self-assembly mechanisms. C3-PLT itself displays nanofiber morphology through H-type π-π stacking, and this nanofiber morphology can be completely transformed into spherical vesicles by host-guest interaction G1, while upon addition of G2 into C3-PLT by means of "exo-wall" electron-transfer interactions, sheet superstructures can be observed. SEM, 1H NMR, DOSY, fluorescence spectroscopy, and viscosity have verified the formation of supramolecular polymers and morphological transitions between C3-PLT with both guests.
In this communication, a new supramolecualr amphiphile was successfully constructed based on water soluble pillar[5]arene and a unique guest which contain a CO2 responsive tertiary amine unit and a UV responsive coumarin group. When guest molecule 1 dispersed in water, it self-assembled into sheet-like structures. Upon bubbling CO2, 1 transformed into 1H due to the tertiary amine unit was protonated, accompany the nano-sheets transformed into vesicles. Further irradiation of 1H with 365 nm light for 3 h, the coumarin group reacted with each other to form bola-type amphiphie 2H. In this case, vesicles collapsed and re-assembled into nano-tubes. However, when addition of WP5 into the solution of 1H, the vesicles transformed into micelles, this is due to the formation of supramolecular amphiphile WP5&1H. Upon irradiation of WP5&1H with 365 nm light for 3 h, nano-ribbons observed instead of micelles in the solution. Notably, nanotubes from 2H could also transform into nano-ribbons after adding WP5. The self-assembly process and the resultant assemblies were characterized by TEM, SEM, DLS, SAXS and NMR technologies. Due to both CO2 and light are pgreenq for living organisms, we anticipated our system can offer the possibilities in pon demandq drug absorption and release.
Flat and crystalline materials with exceptional nonlinear optical (NLO) properties are highly desirable for their potential applications in integrated NLO photonic devices. Graphdiyne (GD), a new two-dimensional (2D) carbon allotrope, has recently evoked burgeoning research attention by virtue of its tunable bandgap along with a high carrier mobility and extended π-conjugation compared with most conventional optical materials. Here, we experimentally probe the third-order nonlinear optical response of GD dispersed in several common solvents (alcohols) using a femtosecond Z-scan technique. The measured nonlinear optical refractive index is in the order of ~10-8 cm2/W, which is approximately one order of magnitude higher than that of most 2D materials. In particular, we find that different NLO responses can be observed from GD when dispersed in different solvents, with the strongest NLO response when dispersed in 1-propanol. It is proposed that some intrinsic properties of the solvents, such as the polarity and viscosity, could influence the NLO response of GD materials. Our experimental results confirm the assumptions on the NLO behavior in GD and demonstrate its great potential for future generations of Kerr-effect-based NLO materials and devices.
Both racemate and enantiomer of a novel double helix, binaphthylcyclooctaterthiophene (BN—COTh), which is a DNA-like molecule constructed by two single helices intertwined with each other via covalent bonds, have been synthesized with two building blocks, cycloocta-tetrathiophene (COTh) and cyclooctadinaphthyldithiophene (CONT) fused together via Negishi coupling reaction. Another homologue, dinaphthylcyclooctaterthiophene (DN-COTh) has been employed together as a model compound. Besides the synthetic work, BN—COTh and DN-COTh have been investigated by studying their crystal structures, spectroscopic behaviors, chiral resolution and chiral characteristics, including circular dichroism (CD) spectra and optical rotations. In addition, the novel crystal of enantiomer of (R, R, R)-BN—COTh has been explored. The enantiomer molecules packing along b-axis to form a larger and extended assembly packing due to intermolecular interactions between the enantiomer molecules and chloroform molecules in crystal.
Incorporation of heteroatoms into the framework of zeolites has become a significant strategy to improve their performance in catalysis and adsorption, because the obtained heteroatom zeolites exhibit quite different properties from the conventional aluminosilicate zeolites in aspects of surface acidity, pore structures, particle size and so on. In this review, the progress on the heteroatom zeolites including their synthesis and application is highlighted. First, the recent advance on the design and synthesis of different heteroatom zeolites is summarized. Special emphasis is placed on the introduction and comparison of three typical methods, including the direct synthesis, post synthesis and improved direct synthesis, for the traditional heteroatom zeolites (such as TS-1, Sn-MFI, Sn-β) and newly-reported heteroatom zeolites (such as W-MFI, Mo-MFI). According to their intrinsic characteristics, the application of heteroatom zeolites in diverse fields, such as production of fine chemicals, air pollution control and biomass conversion is then discussed. Finally, the challenges and perspective on the future development of heteroatom zeolites in low-cost preparation and practical application are proposed.
MXenes, a new family of functional two-dimensional (2D) materials, have shown great potential for an extensive variety of applications within the last decade. Atomic defects and functional groups in MXenes are known to have a tremendous influence on the functional properties. In this review, we focus on recent progress in the characterization of atomic defects and functional group chemistry in MXenes, and how to control them to directly influence various properties (e.g., electron transport, Li+ adsorption, hydrogen evolution reaction (HER) activity, and magnetism) of 2D MXenes materials. Dynamic structural transformations such as oxidation and growth induced by atomic defects in MXenes are also discussed. The review thus provides perspectives on property optimization through atomic defect engineering, and bottom-up synthesis methods based on defect-assisted homoepitaxial growth of MXenes.
Curcurbit[n]uril (Q[n])-based supramolecular frameworks (QSFs) constructed from the outer surface interaction of Q[n]s (OSIQ) have the characteristic of simplicity, diversity and modulability. Their simplicity is reflected in their simple composition and preparation methods used for QSFs. The diversity of supramolecular organic frameworks (SOFs) is reflected in the synthesis methods and structural characteristics of the as-obtained QSFs, as well as the variety of structural directing agents and basic building blocks used to prepare QSFs. The modulability is reflected by the controllable channel size in the QSFs, which can be adjusted using different sizes of Q[n]s. In this work, the first reported cucurbituril Q[6] was selected as the basic building block and three Q[6]-based supramolecular frameworks were obtained from aqueous HCl solutions in the presence of [CdCl4]2- respectively. The OSIQs are the main driving forces for the formation of these frameworks. This study shows the diversity of the QSFs.
A metal-organic photoinduced electron transfer (PET) supramolecular nanoarchitecture comprised of Ru(Ⅱ) bis(terpyridine)-modified pillar[5]arene (electron acceptor) and triazole triphenylamine amyl cyanide (electron donor) has been designed and constructed. Through the comparison of diverse solvents and acceptors, the two conditions, i.e., modification of pillar[5]arene to donor and weak polar solvent are benefit for the occurrence of "efficient PET" because of shorter D-A distance in the presence of pillar[5]arene. Crucially, the fluorescence and PET process of the supramolecular assembly could be further modulated by solvent conversion and another competitive guest. The study provides a supramolecular method to design and construct tunable PET systems and PET-based smart materials.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
