Diganta Bhuyan

Facile synthesis of Fe3O4 nanoparticles on metal organic framework MIL-101(Cr): characterization and catalytic activity

Fe3O4 nanoparticles can be effectively incorporated into the matrix of MIL-101(Cr) to fabricate a Fe3O4@MIL-101 magnetite nanocomposite which behaves as a magnetic nanocatalyst for the solvent free oxidation of benzyl alcohol in the presence of TBHP. The composite material is magnetically separable and can be reused several times.

Magnetically recoverable chitosan-stabilised copper–iron oxide nanocomposite material as an efficient heterogeneous catalyst for azide–alkyne cycloaddition reactions

Chitosan-stabilised copper–iron oxide nanocomposite material is found to be a very efficient recyclable/reusable heterogeneous catalyst for azide–alkyne cycloaddition reaction under mild conditions. The as-synthesized nanocomposite material is magnetically recoverable and reusable for a minimum of four cycles without significant loss in its catalytic activity. The catalytic system is found to be highly useful for the regioselective synthesis of a wide range of 1,2,3-triazoles from various azides and alkynes.

Flower shaped homocentric pencil like ZnO nanorod bundles: synthesis, characterisation and study of their photocatalytic activity

Flower shaped homocentric pencil like ZnO nanorod bundles are synthesized by a hydrothermal method. The PXRD pattern corresponds to the typical wurtzite structures of ZnO, which exhibits excellent activity as a photocatalyst for the degradation of malachite green under solar light irradiation.

Template-free synthesis of Fe3O4 nanorod bundles and their highly efficient peroxidase mimetic activity for the degradation of organic dye pollutants with H2O2

Highly crystalline Fe3O4 nanorod bundles were synthesized via a facile template-free method. The high surface to volume ratio of Fe3O4 nanorods facilitates the excellent activation of H2O2via their peroxidase mimetic activity for the degradation of crystal violet (CV) as a model organic dye pollutant. The self sensitization of CV dye by solar irradiation also indirectly helps in the photo-Fenton-like degradation process.

Facile synthesis of gold nanoparticles on propylamine functionalized SBA-15 and effect of surface functionality of its enhanced bactericidal activity against gram positive bacteria

The facile synthesis of an SBA-15-pr-+NH3.Au0 nano-hybrid material by spontaneous autoreduction of aqueous chloroaurate anions on propylamine functionalized SBA-15 was successfully demonstrated. The as-synthesized SBA-15-pr-+NH3.Au0 nano-hybrid material was well characterized using low and wide angle x-ray diffraction (XRD), N2 adsorption–desorption isotherms, Fourier transform infrared (FTIR), transmission electron microscopy (TEM), scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDX), x-ray photoelectron spectroscopy (XPS), UV-Visible spectroscopy and atomic absorption spectroscopy (AAS). The activity of the nano-hybrid material as a potent bactericidal agent was successfully tested against Gram positive/negative bacteria viz. Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The colony killing percentage of Gram positive bacteria was found to be higher than Gram negative bacteria due to the stronger electrostatic interaction between the positively-charged amine functionality of SBA-15 and the negatively charged functionality of the bacterial cell wall.