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In this work, a novel and simple flexible aromatic multi-carboxylate compound N, N′-(4,4′-biphenylyl) iminodiacetic acid (BP-IDA) was synthesized, with which two new stable metal-IDA gels (denoted as MIG1 and MIG2) with three-dimensional network structures have been prepared successfully by employing Cr3+ and Al3+ as the metal ions, respectively. The rheological performance was investigated by means of dynamic rheology measurement. The morphology and microstructure were characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction technique. Nitrogen sorption isotherm measurement suggests that the MIG1 aerogel has considerable porosity with the Brunauer-Emmett-Teller specific surface area up to 760 m2·g−1. Owing to easy preparation, good stability, and three-dimensional network structure, the as-prepared metal-organic gels will possess potential applications in separation, catalysis, and drug delivery. [ABSTRACT FROM AUTHOR]

An acid-resistant catalyst composed of nickel embedded in N-doped porous carbon is developed for the catalytic hydrogenation of nitrobenzene (NB) to p-aminophenol (PAP). The catalyst, due to a special electron donation from nickel to the N-doped porous carbon, shows an excellent catalytic performance and stability in sulphuric acid solution. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)-wrapped gold nanoparticles (Au NPs) hybrid materials are constructed via one-pot sonochemical synthesis and self-assembly, using ethylene glycol as the reducing agent. The synthesis process above took only 1 h, and the obtained hybrid materials exist as spheres wrapped with gauze-like GO sheets via ionic interaction-based self-assembly. The GO sheets are helpful for the well dispersion of the Au NPs. Furthermore, these materials possess enhanced photocatalytic activity under visible light irradiation, owing to the synergistic effect of the two components in the hybrid materials. Our work may provide a convenient approach to control the size and morphology of the Au NPs for the synthesis of GO-wrapped hybrid materials, which opens up a feasible way to synthesize metal NPs/GO composites. Moreover, this method might lead to developing of a broad class of new functionalized materials wrapped with GO sheets. [ABSTRACT FROM AUTHOR]

A series of benzimidazole-linked porous polymers are obtained by the condensation reaction between the o-aminobenzol end groups of building blocks (2,3,6,7,10,11-hexaaminotriphenylene, 3,3′-diaminobenzidine or 1,2,4,5-benzenetetraamine) and the aldehyde groups of building blocks [terephthalicaldehyde, 4,4′-biphenyldicarboxaldehyde, 1,3,5-tris(4-acetylphenyl)benzene or 1,3,5-tris(4-formylbiphenyl)amine] in one-pot synthesis without employing any catalyst or template. The existence of the imidazole ring in the obtained polymers could be identified by Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy. The sphere-shaped morphology of the obtained polymers is observed through scanning electron microscopy. The polymers possess Brunauer-Emmett-Teller specific surface area values over 600 m2·g−1, showing hydrogen storage (up to 1.6 wt%, at 77 K and 1×105 Pa) and carbon dioxide capture (up to 12.6 wt%, at 273 K and 1×105 Pa) properties. Such polymers would possess good performance in the applications of gas storage and separation. [ABSTRACT FROM AUTHOR]

Cyclodextrins (CDs) are regarded as one kind of the most important and promising macrocyclic oligosaccharides, which contain hydrophobic internal cavities capable of hosting various guest molecules. CDs are water-soluble, non-toxic, commercially available as well as low-cost. Because of these favorable characteristics, cyclodextrin chemistry has created a great number of interesting works covering different fields, in particular CD-based porous nanocapsules (CDPNCs). Chemical cross-linking is an important way developed to prepare CDPNCs. CDPNCs can be obtained using different cross-linkers and preparation methods, such as homogeneous method, miniemulsion polymerization, and emulsion-solvent evaporation method. Because of cross-linking, a three-dimensional network is built which forms the porous structure in CDPNCs with the cavities of CDs. Attributed to the porous structure, CDPNCs exhibit excellent performances in encapsulation of targeted molecules and realization of controllable release, indicating a promising prospect in applications such as drug delivery systems and environment protection. [ABSTRACT FROM AUTHOR]

Cyclodextrins (CDs) show functionality, biocompatibility, and host-guest inclusion capacity with a variety of molecules. These unique properties offer great potential for the exploitation of CDs as drug delivery systems. An easy, green, and effective synthetic approach was described to develop CD-based porous nanospheres (CDPNSs) with a size distribution from 100 to 400 nm. A new cross-linker tris(2-aminoethyl)amine was used to cross-link modified β-CD at room temperature. The resulting CD-based polymers (CDPs) were reshaped from a random morphology into a spherical shape during a dialysis process, and CDPNSs were obtained. The morphologies of CDPs and CDPNSs were observed with scanning electron microscopy. The average diameter and the size distribution of CDPNSs were determined by dynamic light scattering. The structures of the resulting products were characterized by using Fourier transform infrared spectroscopy, 1H NMR spectroscopy, solid-state 13C CP/MAS NMR spectroscopy, and X-ray diffraction. Furthermore, a study was conducted on drug loading and in vitro release behavior of CDPNSs, which was monitored by ultraviolet spectroscopy. The prepared CDPNSs show the potential as drug delivery systems. [ABSTRACT FROM AUTHOR]

Review: synthesis using different cross-linkers and preparation methods; 86 refs. [ABSTRACT FROM AUTHOR]

A simple and efficient route for quantum dot (QDs) patterning using self-assembled monolayers (SAMs) as templates is described. By means of a laser direct-writing (LDW) technique, SAMs of octadecylphosphonic acid formed by adsorption on native oxide layer of titanium film were patterned through laser-induced ablation of the SAM molecules. This technique allows the creation of chemical-specific patterns accompanied by slight change in the topography. Using atomic force microscopy and friction force microscopy, the dependence of feature size and characteristics on the irradiation dose was demonstrated. Upon immersion of a substrate with patterned SAMs bearing thiol as the terminal group into a dispersion of QDs resulted in the assembly of QDs on the specific thiol-terminated areas. Patterns of QDs with different photoluminescent wavelength were generated. The LDW technique, which is convenient and flexible due to its path-directed and maskless fabrication process, provided a new powerful approach for patterning materials on surfaces for various applications. [ABSTRACT FROM AUTHOR]

Accurate measurement of inter-peptide interactions is beneficial for in-depth understanding disease-related protein folding and peptide aggregation, and further for designing and selecting potential peptide drugs to the target antigen. Herein, we demonstrate a 3D polyrotaxane (PRX) surface for detecting peptides interactions by surface plasmon resonance imaging (SPRi). This surface is supramolecular self-assembly monolayer (SAM) structure fabricated by threading α -cyclodextrans ( α -CD) through a linear polyethylene glycol (PEG) chain fixed on gold chip surface to form pseudopolyrotaxane, and further capping the pseudopolyrotaxane with bulky terminated group to form PRX film. The hydroxyl groups of α -CD can provide more active sites to increase molecules immobilization density, and PEG chain has unique protein non-fouling feature. We chose Alzheimer's disease marker β -amyloid 40 (A β 40) as model peptide, and detected the interaction between it and its inhibitors KLVFFK6 by SPRi. As a striking result, the specific adsorption of KLVFFK6 solution at the concentration of 352 μM on A β 40-PRX was 700 RU, whereas PEG SAM surface gave no significant binding. Interaction between other lower molecular weight peptides was detected via PRX surface, and the relatively weak interactions ( K D =1.73×10 −4 M) between LPFFD ( Mw =0.6 kDa) and amylin20-29 ( Mw =1.0 kDa) are successfully detected. [ABSTRACT FROM AUTHOR]

Fluorine-containing 2D polymer (F-2DP) film is a desired system to regulate the charge transport in organic electronics but rather rarely reports due to the limited fluorine-containing building blocks and difficulties in synthesis. Herein, a novel polar molecule with antiparallel columnar stacking is synthesized and further embedded into an F-2DP system to control over the crystallinity of F-2DP film through self-complementary π-electronic forces. The donor-accepter-accepter'-donor' (D-A-A'-D') structure regulates the charge transportation efficiently, inducing multilevel memory behavior through stepwise charge capture and transfer processes. Thus, the device exhibits ternary memory behavior with low threshold voltage (V th1 of 1.1 V, V th2 of 2.0 V), clearly distinguishable resistance states (1:10 2 :10 4 ) and ternary yield (83%). Furthermore, the stepwise formation of the charge complex endows the device with a wider range to regulate the conductive state, which allows its application in brain-inspired neuromorphic computing. Modified National Institute of Standards and Technology recognition can reach an accuracy of 86%, showing great potential in neuromorphic computing applications in the post-Moore era., (© 2024 Wiley‐VCH GmbH.)

Ionic liquids and poly(ionic liquid)s have been successfully converted into nitrogen-doped porous carbons with tunable surface area up to 1200 m²/g at high temperatures in air. Compared to conventional carbonization process conducted under inert gas to produce nitrogen-doped carbons, the new production method was completed in a rather shorter time without noble gas protection.