Swarnima Rawat; Nilanjal Misra; Virendra Kumar; Shubhangi Atmaram Shelkar; Narender Kumar Goel; Rakesh Kumar Singhal; Lalit Varshney
Abstract
A robust and reusable Copper Nanoparticles Immobilised Catalytic Reactor (Cu-NICaR) system was fabricated by immobilising Copper Nanoparticles (Cu NPs) onto a radiation functionalized polymer support. Gamma radiation induced simultaneous irradiation grafting process was employed for introducing poly-glycidyl ...
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A robust and reusable Copper Nanoparticles Immobilised Catalytic Reactor (Cu-NICaR) system was fabricated by immobilising Copper Nanoparticles (Cu NPs) onto a radiation functionalized polymer support. Gamma radiation induced simultaneous irradiation grafting process was employed for introducing poly-glycidyl methacrylate (poly(GMA)) chains onto non woven PE-PP matrix. Optimization of the grafting process was carried out by studying the effect of experimental parameters, such as absorbed dose, monomer concentration and solvent polarity on grafting yield. The poly(GMA)-g-PE-PP matrix was used as a functional polymer support for Cu NPs, synthesised under optimized conditions using NaBH4 as reducing agent. Characterization of the samples was carried out by UV-Visible spectrophotometer, Fourier Transform Infrared (FTIR) Spectroscopy, X-ray fluorescence (XRF), Thermogravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM). Catalytic activity of Cu NPs immobilised poly(GMA)-g-PE-PP catalytic system was studied by spectrophotometrically monitoring the catalytic reduction of p-nitrophenol (PNP), using NaBH4 as reducing agent. The Cu NPs-immobilised-poly(GMA)-g-PE-PP was observed to exhibit excellent catalytic activity both in batch process (12 cycles over a period of 30 days) as well as in fixed bed column reactor mode, without significant loss of activity.
K. Hareesh; R. P. Joshi; V. N. Bhoraskar; S. D. Dhole
Abstract
Gold-reduced graphene oxide (AG) nanocomposites were synthesized by one-step gamma radiation assisted method. UV-Visible spectroscopic results showed the disappearance of 230 nm peak and appearance of a peak around 269 nm in AG nanocomposite confirming the reduction of GO, and also a peak around 534 ...
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Gold-reduced graphene oxide (AG) nanocomposites were synthesized by one-step gamma radiation assisted method. UV-Visible spectroscopic results showed the disappearance of 230 nm peak and appearance of a peak around 269 nm in AG nanocomposite confirming the reduction of GO, and also a peak around 534 nm appears confirming the formation of gold nanoparticles (AuNPs). X-ray diffractogram results of AG nanocomposite showed a broad peak around 25° corresponding to reduced graphene oxide and also it showed peak corresponding to face centered cubic structured AuNPs corroborating the UV-Visible spectroscopic results. The decoration of AuNPs of size 6 nm on reduced graphene oxide sheet was revealed by transmission electron microscopic results. X-ray photoelectron spectroscopic results confirmed the removal of oxygen functional groups from graphene oxide and formation of Au 4f in AG nanocomposite. The synthesized AG nanocomposite showed enhanced catalytic reduction of 4-Nitrophenol compared to rGO and AuNPs due to synergistic effect of individual component. Gamma radiation assisted method synthesis of Au-rGO nanocomposite may emerge as one-step synthesis that don’t require high temperature or harsh reducing agent.
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