M.K. Debanath; R.K. Saha; S.M. Borah; E. Saikia; K.K. Saikia
Abstract
In our present investigation, we have synthesized starch-capped Cu doped ZnO (ZnO:Cu) nanoparticles (NPs) by simple wet chemical method and studied their structural, optical and antibacterial effects on/against Gram-positive and Gram-negative bacteria. Chemically synthesized nanoparticle have been characterized ...
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In our present investigation, we have synthesized starch-capped Cu doped ZnO (ZnO:Cu) nanoparticles (NPs) by simple wet chemical method and studied their structural, optical and antibacterial effects on/against Gram-positive and Gram-negative bacteria. Chemically synthesized nanoparticle have been characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive analysis of X-rays (EDAX), high resolution transmission electron microscopy (HRTEM), UV-vis absorption spectroscopy and photoluminescence (PL) spectroscopy for their structural and optical properties. Antibacterial properties have been studied by Staphylococcus aureus (S. aureus, Gram-positive) and Escherichia coli (E. coli, Gram-negative) bacteria. XRD study showed hexagonal wurtzite crystal structure of the prepared ZnO:Cu and nanoformation of the as-synthesized NPs. Nanoparticle formation have been finally confirmed by HRTEM analysis. Antibacterial studies showed excellent resistance of ZnO:Cu to S. aureus and E. coli respectively. Copyright © 2018 VBRI Press.
Ioannis Tsiaoussis; Nikos D. Charisiou; Maria A. Goula; Lazaros Tzounis; George Vourlias; oannis V. Yentekakis; Remi Chassagnon; Valerie Potin; Bruno Domenichini
Abstract
In the present work, we investigated the structural morphology of carbon species deposited on nickel catalysts supported on CeO2-ZrO2 (18.8 wt.% ceria), prepared by wet impregnation, during the dry reforming of methane (DRM) reaction by using Thermo-gravimetric Analysis (TGA), Raman Spectroscopy, ...
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In the present work, we investigated the structural morphology of carbon species deposited on nickel catalysts supported on CeO2-ZrO2 (18.8 wt.% ceria), prepared by wet impregnation, during the dry reforming of methane (DRM) reaction by using Thermo-gravimetric Analysis (TGA), Raman Spectroscopy, X-ray diffraction (XRD), High Resolution TransmissionElectron Microscopy (HRTEM) and Scanning Transmission Electron Microscopy- Energy dispersive spectroscopy(STEM-EDS). TGA results show that the amount of deposited carbon decreases upon increasing reaction temperature, which is consistent with the thermodynamics of the reactions responsible for carbon formation, and Raman analysis points to a simultaneous increase in its graphitization degree. XRD measurements reveal the existence of 2H-Graphite and TEM imaging mode as well as SAED patterns depict that in all temperatures under which the catalysts were tested (550, 650, 750 and 800 oC), the formation of multi wall carbon nanotubes (MWCNT). HRTEM observations also reveal that the Ni nanoparticles are often enclosed by the MWCNT. HRTEM images identify nanocrystalline areas with a tetragonal phase, P42/nmc(137), of Ce1-xZrxO2, and STEM-EDS analysis at the nanometer scale confirms a correlation between Ce and Zr in the average atomic ratio (% ), 1 to 5.19 - 6.94 respectively. The results presented herein confirm that biogas mixtures can be used as precursors for the production of MWCNTs. Copyright © 2017 VBRI Press
