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The design and preparation of functionalized composite adsorbent materials are of key importance for wide environmental fields. This study demonstrates a new route to fabricate hybrid nanomaterial by encapsulating Schiff base molecules into sulfonate groups charged polystyrene beads (PS). The prepared composite adsorbent, polystyrene-Schiff base ((PS-SB)) nanocomposites, showed more preferable Cu(II) ion removal capacity in the presence of Mg 2+ and Ca 2+ co-ions in solutions. Comparatively, the obtained (PS-SB) composites with inner well-dispersed Schiff base molecules and high sorption ability demonstrated much faster breakthrough for Cu(II) ion removal than PS beads, mainly due to the electrostatic forces and coordinating reaction of Schiff base groups with Cu(II) ion. In addition, the used composite adsorbent material could be easily regenerated by HCl-NaCl solution for repeated utilization without obvious capacity loss. Present research work showed that charged functional groups in host nanostructures improved the dispersion and connection of anchored organic molecules, enhancing the removal capacity of targeted metal ions. Suitably designed guest molecules in composite structures are crucial in the preparation of excellent nanocomposites for the removal of toxic metal ions and other charged pollutants from wastewater. [ABSTRACT FROM AUTHOR]

Facile preparation and UV stabilization of electrospun poly(e-caprolactone) (PCL)/2-methyl-3-(trimethoxysilyl) propylester (M8POSS)/pentaerythritol tetrakis(3-mercaptopropionate) (PETM) composite fibers via thiol-ene click reaction were investigated. The morphological studies clearly showed the M8POSS and PETM macromers were excluded from PCL crystalline phase during electrospinning. The cross-linking reaction occurs in the amorphous phase of PCL fibers and possibly the fiber surface. By locking amorphous PCL chains into the cross-linked M8POSS and PETM through thiol-ene click reaction, we are able to fabricate PCL/POSS composite fibers, which can remain structural stability under UVC for longer period of time. The facile fabrication of the composite fibers via thiol-ene click reaction reported here provided valuable insight into not only the surface coating of medical devices but also new biocompatible composite materials. [ABSTRACT FROM AUTHOR]

Diabetes is one of the global chronic diseases, which is mainly caused by the abnormal increase of blood sugar level. Therefore, it is particularly important to monitor glucose in real time. In this work, based on the principle that phenylboronic acid can react with diol rapidly and reversibly in aqueous medium, phenylboronic acid functionalized reduced graphene oxide (rGO-PBA) and polyhydroxy modified carbon spot fluorescent probe (CD1) were designed for detecting important glucose molecules. Among them, reduced graphene oxide (rGO) has high specific surface area and strong fluorescence quenching performance. When CD1 is close to the surface of rGO-PBA, the fluorescence of carbon dots was quenched. With the addition of glucose, the fluorescence of carbon dots increased continuously. The detection of small molecule glucose can be realized quickly and sensitively by using the "on" and "off" strategies of fluorescence. [Display omitted] • Develop new rGO-PBA and polyhydroxy modified carbon spot fluorescent probe. • Show high specific surface area and strong fluorescence quenching performance. • Provide important strategies and ideas for carbon spot fluorescent probe. [ABSTRACT FROM AUTHOR]

• Develop new composite materials via non-covalently assembly strategy. • Self-assembled composite prepared in an eco-friendly and effective manner. • Composite exhibit high selectivity for Cu(II) ion removal and good stability. • Significant potentials in self-assembled composite absorbent design. Functionalized nanocomposite adsorbents based on multiple sites of sorption are critically important for advancing removal of heavy metal ions. Herein, a non-covalently assembly strategy for fabrication of efficient adsorbent with multiple-site adsorption capability is introduced. A novel hybrid nanomaterial was fabricated by encapsulating chitosan molecules (CS) into charged polystyrene resin (PS) through electrostatic adsorption. The resulting hybrid absorbent (PS-CS) demonstrates highly efficient sorption toward cupric ion, mainly because of the electrostatic interactions of sulfonate group and chelation of NH 2 and OH groups of chitosan with cupric ion. Meanwhile, the obtained composites with interior well-dispersed chitosan molecules give specific selectivity for cupric ion in the present of divalent competition ions such as Ca2+ and Mg2+. Adsorption equilibrium data can be described with Freundlich isotherms model and the pseudo-second-order model. The kinetic rate constants have been determined for PS and PS-CS nanocomposite. In this paper, it is suggested that charged groups in host materials not only enhance the fixation and dispersion performance of embedded molecules but provide more target sites for nanocomposite, thus enhancing capacity for sorption of metal ions. Therefore, construction of multi-target nanocomposites provides conceivably promoted development of highly efficient adsorbents for toxic metals abatement. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • develop new electrospun composite materials via SVA treatment. • self-assembled composite prepared in an eco-friendly and effective manner. • composite exhibits high-efficient catalytic capacities and good stability. • significant potentials in self-assembled composite films design. Abstract A new ternary poly(ε-caprolactone) (PCL)/poly(ethylene oxide) (PEO)@AuNPs composite material with high catalytic activity and favorable structural stability has been successfully prepared. The prepared PCL/PEO composite fibers by electrospinning have been treated with an easy-to-operate solvent vapor annealing (SVA) process, demonstrating wrinkled fiber nanostructures, promoting the significantly high specific surface area and more active sites in the surface of electrospun fiber. Then NaBH 4 was used as a reducing agent to reduce HAuCl 4 to form gold nanoparticles, resulting in the targeted PCL/PEO@AuNPs composite material. The obtained PCL/PEO@AuNPs composites demonstrated potential catalytic ability and good reusability in the catalytic reduction of 4-nitrophenol and 2-nitroaniline systems, showing promising and wide applications in catalytic composite materials and self-assembled films. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Develop new polypyrrole-diamond core-shell composite materials. • Self-assembled composite prepared in an eco-friendly and effective manner. • Composite exhibit elevated electrochemical performances. • Significant potentials in polypyrrole composite material design. Abstract The fabrication of graphitized diamond covered with polypyrrole (D@G@PPy) core-shell nanocomposites has been achieved by using a superficial electrochemical polymerization and self-assembly strategy. The conductivity of the core-shell nanocomposites was influenced by polymerization time, current as well as the concentration of ions. The obtained excellent conductivity appeared with the current of 0.6 mA and the duration time of 1 h. In addition, the corresponding enhanced electrochemical performance of polypyrrole grown on graphitized diamond substrate is demonstrated compared with pristine polypyrrole. The morphologies of the obtained composites were illuminated through scanning electron microscopy (SEM) and the conductivity was demonstrated by electrochemical impedance spectroscopy (EIS). The characteristic peaks of polypyrrole and qualitative analysis of surface elements have been investigated by Raman spectra and X-ray photoelectron spectroscopy (XPS). The present research could demonstrate a new aspiration for the design and preparation of novel polypyrrole core-shell composites materials. [ABSTRACT FROM AUTHOR]

The chemical modification and organized self-assembly of MXene-based nanocomposites demonstrate critical importance to a wide range of material applications. Herein, we have investigated the preparation of new hierarchical core-shell type MXene-based composite materials for high-efficient dye removal in wastewater treatment via layer-by-layer (LbL) strategy. From the carboxyl functionalization of the MXene material, the negative functional groups were obtained on the surface of the shell composite layer. Carboxyl functionalized MXene materials are immersed in polyimide and polyacrylic acid solution respectively, which leads to formation of shell structure on the surface of MXene layer. Alternating self-assembly processes in the solutions of the polyimide and polyacrylic acid polymers are investigated until the desired number of shell layers is fabricated around MXene layer structures. Finally, the core-shell nanocomposites were characterized by morphological and spectral techniques, demonstrating that the core-shell nanocomposites have more reaction sites and mesoporous structures. The as-obtained core-shell nanocomposites were evaluated with well adsorption capacities via three kinds of dyes. Thus the study of MXene based composites assembled by LbL provides a new choice for the application of MXene composite nanomaterials in wastewater treatment. [ABSTRACT FROM AUTHOR]

The design and preparation of functional beta-cyclodextrin-based composite films are of key importance for wide application fields. This study demonstrates a new route to construct composite films by Langmuir-Blodgett (LB) method via cholesterol-modified beta-cyclodextrin derivative (CD-CHOL). The inclusion complex formation of CD-CHOL and azobenzene derivative (N-Azo) at the air/water interface was investigated. It has been found that the interfacial host-guest recognition could easily occur in the in situ formed CD-CHOL/N-Azo composite films and relatively difficult to occur in the ex situ immersed composite films, because there exist host-guest interaction as well as intermolecular hydrogen bonding interaction. The inclusion complex formation was confirmed by changes in the surface pressure-area isotherms, circular dichroism (CD) and UV–vis spectra of the transferred LB films. And the solvent effect of the composite CD-CHOL/N-Azo films was also investigated, indicating that host-guest interaction between N-Azo and CD-CHOL could occur rather in the nonpolar solvent than the polar solvent. The present research work about beta-cyclodextrin-based composite films by LB method may provide new exploration to prepare organized composite films and demonstrate potential applications in many fields. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)-based nanocomposite films via facile and appropriate self-assembly methods have demonstrated many potential applications in wide fields. This study demonstrates a facile and clean route to prepare graphene oxide-dye composite films using Langmuir-Blodgett (LB) technique at room temperature. By electrostatic interaction between cationic dye molecules and negatively charged GO sheets as well as π-π interactions, GO-dye composite LB films were formed spontaneously. As a soft platform for dye molecules, GO sheets induce dye molecules to self-assemble and form highly ordered structures containing H-aggregates and/or J-aggregates. The morphological characterization results show the formation of GO-dye composite films with smooth and dense surfaces. And the spectral results reveal that dye molecules stack in well-organized aggregates on the surface of GO sheets corresponding to monomers in bulk solution. The present research work about GO-dye composite films by LB method may provide new clues to prepare organized composite films and demonstrate potential applications in many fields. [ABSTRACT FROM AUTHOR]

Highlights: [•] New binary organogels in single or mixed solvents were prepared. [•] Various nanostructures and hydrogen bonds from different solvents were investigated. [•] Solvents and molecular skeletons are crucial to the gelation behaviors. [•] Suitable single/volume ratios in mixed solvents are favorable for gel formation. [Copyright &y& Elsevier]

• Develop new composite film materials via non-covalent assembly strategy. • Self-assembled GO composite films prepared in an effective manner. • Composite films contain highly ordered aggregate structures. • Significant potentials in self-assembled composite film design. Constructing graphene oxide (GO)-based 2D nanomaterials via facile and appropriate methods have aroused much attention due to their potential applications in many fields. Herein, by Langmuir-Blodgett (LB) technique, we have successfully fabricated GO-based films composited with porphyrin molecules. By the reaction of diazotization and Fischer osazone, different surface states of GO sheets with sulfonate groups were obtained. The amphiphilic GO and surface modified GO sheets could spontaneously form composite films at the air/water interface with porphyrin molecules (TMPyP) by electrostatic interactions and π-π stacking. Since the sheets can perfectly float on the interface, the TMPyP molecules were adsorbed on the floating-layers and self-assembled into highly ordered J-aggregate structures. The morphological characterization results showed the composite films with smooth and dense surface. Due to the different surface state of the nanosheets, the aggregate states of porphyrin molecules were different which could be demonstrated in the UV–vis spectra. The results indicated that the induction of sulfonate groups and the types of oxygen-containing groups have played important roles for regulating the aggregate state of porphyrin molecules. [ABSTRACT FROM AUTHOR]

• Develop new self-assembled hydrogels via host-guest polymers. • Self-assembled hydrogels prepared in an eco-friendly and effective manner. • Hydrogels exhibit highly efficient MB and BPA removal. • Significant potentials in self-assembled composite absorbent design. In this study, new self-assembled hydrogels constructed by cyclodextrin polymer (P-CD)/ferrocene-modified poly acrylic acid (PAA-Fc) were designed and prepared via host-guest interactions. These obtained hydrogels were characterized by different methods such as Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric (TG) and specific surface area tests. SEM images confirmed that the prepared hydrogels had a three-dimensional (3D) porous network structure with pore size ranging from several hundred nanometers to several tens of micrometers. The network structure of the hydrogels could be adjusted by varying the concentrations of P-CD. In addition, the gel-sol transition process would occur when the gel has redox stimulation. In particular, the prepared hydrogels have different adsorption mechanisms in the adsorption of poisonous organic molecules, including bisphenol A (BPA) and methylene blue (MB). It was found that the adsorption process had high pH dependence. The adsorption data for BPA and MB were found to be consistent with the pseudo-first-order model and the pseudo-second-order model, respectively. The maximum adsorption capacity of the hydrogel material reached 23.61 mg/g for BPA and 24.64 mg/g for MB. Present hydrogels removed BPA mainly via host-guest interaction and removed MB by hydrogen bonding and electrostatic interaction. Present obtained hydrogels provided new clues for the design of environmentally friendly hydrogel adsorbents. [ABSTRACT FROM AUTHOR]