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Abstract: Herein we report the design of antimicrobial nanohybrids, f-MWCNTs-CdS and f-MWCNTs-Ag2S developed by covalent grafting of cationic hyperbranched dendritic polyamidoamine (PAMAM) onto multiwalled carbon nanotubes (MWCNTs) and successive deposition of CdS and Ag2S quantum dots (QDs). The CdS and Ag2S QDs were in situ deposited on PAMAM grafted MWCNTs instead of anchoring the pre-synthesized QDs. The fourth generation, amine terminated hyperbranched PAMAM was grafted on MWCNTs, which was achieved through repetitive reactions of Michael addition of methylmethacrylate to the surface amino groups and amidation of terminal ester groups with ethylenediamine. The covalent grafting of PAMAM onto MWCNTs and the consecutive conjugation of CdS and Ag2S QDs were characterized using Fourier transform infrared spectroscopy, elemental analysis, powder X-ray diffraction, Raman spectroscopy, transmission electron microscopy and energy dispersive spectroscopy. The antibacterial activity of f-MWCNTs-CdS and f-MWCNTs-Ag2S nanohybrids was evaluated against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus and the results were compared with the activity of carboxylated MWCNTs, PAMAM grafted MWCNTs, PAMAM dendrimer, and CdS and Ag2S QDs. It was found that the germicidal action of MWCNTs was enhanced by grafting of PAMAM, which was further improved with immobilization of CdS and Ag2S QDs. [Copyright &y& Elsevier]

Abstract: Herein a facile hydrothermal approach is used to construct carbon coated TiO2 nanoparticles employing dextrose as the source of carbon. The procedure is operated at a low temperature of 200°C. Fourier infrared spectroscopy demonstrated the successful coating of carbon on TiO2 nanoparticles. The phase composition of TiO2 and carbon coated TiO2 nanoparticles were studied using X-ray diffraction and the surface morphology was analyzed by scanning and transmission electron microscopy. The existence of carbon coating on TiO2 nanoparticles was revealed by thermogravimetric analysis through different thermograms exhibited for TiO2 and carbon coated TiO2 nanoparticles. The reported method offers a simple and efficient approach for production of carbon coated TiO2 nanoparticles. [Copyright &y& Elsevier]

Abstract: Two novel ternary nanocatalysts, f-MWCNTs-CdS and f-MWCNTs-Ag2S were successfully constructed by covalent grafting of fourth generation (G4) hyperbranched, crosslinked poly(amidoamine) (PAMAM) to carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) and subsequent deposition of CdS or Ag2S quantum dots (QDs). The structural transformation, surface potential, and morphology of functionalized MWCNTs (f-MWCNTs) and nanocatalysts were characterized by UV–vis spectrophotometer, Fourier transform infrared spectroscopy, powder X-ray diffraction, Raman spectroscopy, thermogravimetric analysis, scanning electron microscopy and energy dispersive spectroscopy. Transmission electron microscopy reveals the effective anchoring of QDs on f-MWCNTs. The catalytic activity of nanocatalysts was evaluated by photodegradation of methyl orange under illumination of UV light. The coupling of MWCNTs, PAMAM and CdS or Ag2S QDs significantly enhanced the catalytic efficiency of nanocatalysts. The rate constants for degradation of methyl orange in presence of nanocatalysts were calculated using the Langmuir–Hinshelwood model. Overall, the excellence in photodegradation was accomplished by hybridizing f-MWCNTs with CdS or Ag2S QDs. [Copyright &y& Elsevier]

The title compound, [Er(C5H7O2)3(C12H8N2)], is a mixed-ligand metal–organic precursor for chemical vapour deposition, with the Er atom being eight-coordinate. The coordination polyhedron, described as a distorted square anti­prism, is formed by three bidentate (chelating) acetyl­acetonate residues and a phenanthroline ligand in the apical positions. Mol­ecular assembly via C—H⋯O hydrogen bonds generates a sheet structure in the ac plane. Weak co-operative C—H⋯π inter­actions form mol­ecular dimers and contribute to the stability of the inter­sheet packing. The supra­molecular assembly contains voids which form hydro­phobic porous channels, surrounded by a cluster of dimers. [ABSTRACT FROM AUTHOR]

The title compound, [Ni(C8H13O3)2(C5H5N)2]·C6H6, a potential metal–organic chemical vapour deposition (MOCVD) precursor, crystallizes with half a molecule of the complex and half a molecule of benzene in the asymmetric unit, both molecules being centrosymmetric. The Ni atom is at the origin (0, 0, 0), while the centroid of the benzene solvent molecule is at another centre of symmetry (0,  ,  ). The Ni atom has a distorted octahedral environment, with four O atoms from the bidentate tert-butyl-3-oxobutanoate ligand units in the axial positions and the two N atoms of the pyridine ligands at the apical positions. C—H...π contacts [3.021 (4) Å] between solvent benzene and the pyridine ligand, along with π–π stacking interactions [3.896 (1) Å] between adjacent pyridine ligands, result in a packing motif along the c axis. [ABSTRACT FROM AUTHOR]

In the title complex, [Al(C8H13O3)3], a potential metal-organic chemical vapour deposition (MOCVD) precursor, three bidentate ligand mol­ecules are bound to the metal atom, forming an octa­hedral geometry. Two non-planar six-membered chelate rings adopt screw-boat conformations, while the third ring has a conformation that lies about halfway between an envelope and a screw-boat. [ABSTRACT FROM AUTHOR]

• Naturally available 3D diatoms (DE) combined with MIL100(Fe) to form MIL100(Fe)-DE hybrid materials. • MIL100(Fe)-DE as drug carrier controlled the drug release up to 23 days. • MIL100(Fe)-DE used as heterogeneous Fenton's catalysis showed 99% of MB degradation efficiency. • MIL100(Fe)-DE showed Pb2+ removal of 96.45% efficiency and high adsorption capacity of 155 mg/g with excellent reusability. • MIL100(Fe)-DE explored for various dye removal applications with removal efficiency of 98, 96, 76 and 75% respectively. Metal-organic frameworks (MOFs) emerged as one of the promising functional materials for broad applications. To improve the sustainability of their synthetic route and extend their applications are still demanding and challenging task. Herein, to address this problem, we report practical use of "eco-friendly" approach to create new type of hybrid materials by combining MOFs with naturally available hierarchical diatom biosilica (DE) acts as 3D porous scaffolds. This combination of high surface area, an unique 3D diatom architecture with 2D MOFs structure with specific chemical functionalities –OH, –COOH and Fe atoms confined in MIL-100(Fe)-DE hybrid materials and explored for a wide range of applications like drug delivery, catalyst support and environmental adsorbents. To prove drug delivery application for MIL-100(Fe)-DE, isoniazid (INH) anti-TBC (tuberculosis) drug is selected as typical drug model showing an enhanced drug loading capacity of 9.6 ± 1.6% and an extended in vitro controlled drug release performances over 23 days. This is significant improvement of short drug release characterstics and biological half life of INH (1–4 h) that limits to rich full therapeutic benefits for treatment of TBC. A heterogeneous Fenton's catalysis study of MIL-100(Fe)-DE showed a rapid degradation of Malachite green (MG) dye within 60 min with degradation efficiency of 99.02 ± 1.3%. To prove environment remediation performances at 25 °C and in pH 6, MIL-100(Fe)-DE displayed efficient removal of Pb2+ with removal efficiency of 96.45 ± 2.1%, high adsorption capacity of 155 mg/g and the improved partition co-efficient (PC) was 87.32 mg.g−1.µM−1 for Pb2+ of (50 mg/L) with excellent reusability. Finally, MIL-100(Fe)-DE hybrid was tested for the removal of cationic dyes such as methylene blue (MB), rhodamine B (RhB) and anionic dyes like congo red (CR) and erichrome black T (EBT) showing 96.10 ± 1.3, 75.11 ± 1.95, 98.11 ± 1.7 and 76 ± 1.88% of removal efficiency respectively. [ABSTRACT FROM AUTHOR]

The synthesis of polyaniline (PANI) nanospheres by a simple template-free method has been described. The polymerization of aniline in aqueous medium was accomplished using ammonium persulfate without any protonic acid. The UV-vis spectrum of PANI nanospheres displayed the characteristic absorption peak of π-π* transition of the benzenoid ring at 355 nm. The oxidation state of PANI nanospheres was identified with FT-IR spectroscopy by comparing the two bands at 1582 (ring stretching in quinoid unit) and 1498 cm(-1) (ring stretching in bezenoid unit). The X-ray diffraction patterns demonstrated the low crystalline nature of PANI nanospheres. The morphology of PANI nanospheres was spherical and the mean diameter of nanospheres was found in the range of 3-12 nm. The thermal behavior of PANI nanospheres was studied by thermogravimetric analysis. The effect of doping of HCl and H(2)SO(4) on PANI nanospheres was studied by measuring the current as a function of time of exposure. The high electrical conductivity of 6×10(-2) S cm(-1) was obtained for PANI nanospheres at their optimum doping state by 100 ppm HCl.