Browsing by Author "Seyrankaya, Abdullah"

Now showing 1 - 3 of 3

Green Synthesis and Characterization of Camellia Sinensis Mediated Silver Nanoparticles for Antibacterial Ceramic Applications
(Elsevier Science Sa, 2020) Gol, Fatma; Aygun, Aysenur; Seyrankaya, Abdullah; Gur, Tugba; Yenikaya, Cengiz; Sen, Fatih
This study focuses on the use of green synthesized silver nanoparticles (Ag-NPs) with the aid of Camellia sinensis (black tea) extract to provide antibacterial activity on ceramic structure. The synthesized Ag nanoparticles were added to the glaze used in the ceramic structures and mixed homogeneously. The homogeneous mixture was characterized by transmission electron microscopy (TEM), X-Ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-Vis spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR) techniques. The SPR band of the synthesized biogenic Ag NPs was observed as 422 nm during the reaction at mom temperature. TEM analysis revealed that Ag NPs were spherical and a particle size between 10 and 20 nm. Furthermore, the antibacterial properties of the homogeneous mixture (Ag NPs and glaze) were tested against Escherichia coli (E. coli, Bacillus subtilis (B. subtilis), Staphylococcus aureus (S. aureus), Methicillin-resistant Staphylococcus aureus (MRSA) bacteria. Biogenic Ag NPs at a concentration of 100 mu g/ml were observed to have 90%, 75%, 75%, 80% lethal effects against S. aureus, MRSA, B. Subtilis, and E. Coli bacteria, respectively. The antibacterial results of Ag NPs obtained with the help of Camellia sinensis show that they may have potential application and development in the field of ceramics. In addition, the antibacterial activity of commercially available antibiotics and the prepared Ag NPs were analyzed in ceramic glazes.
Green Synthesis and Characterization of Camellia Sinensis Mediated Silver Nanoparticles for Antibacterial Ceramic Applications (Vol 250, 123037, 2020)
(Elsevier Science Sa, 2021) Gol, Fatma; Aygun, Aysenur; Seyrankaya, Abdullah; Gur, Tugba; Yenikaya, Cengiz; Sen, Fatih
Palladium Based Bimetallic Nanocatalysts: Synthesis, Characterization and Hydrogen Fuel Production
(Elsevier Sci Ltd, 2023) Ni, Kaijie; Wu, Yingji; Karimi, Fatemeh; Gulbagca, Fulya; Seyrankaya, Abdullah; Altuner, Elif Esra; Sen, Fatih
In this study, Palladium dopped Copper oxide nanoparticles (CuO@Pd NPs) were synthesized by an environmentally friendly green synthesis method for hydrogen production experiments. Characterizations of synthesized nanoparticles; UV-vis Spectroscopy to characterize the optical properties, Scanning Electron Microscopy (SEM) to determine the morphology and particle size of the particles, Fourier Transform Infrared Spectroscopy (FTIR) for the analysis of organic groups, and X-ray Diffraction Spectroscopy (XRD) for the crystal lattice type analysis were used. As a result of the UV-vis Spectroscopy characterization of the synthesized nanoparticles, an absorption peak compatible with metals visible at 422 nm was observed. According to the XRD analysis results, the crystal size observed in the cubic phase was calculated as approximately 4.426 nm. According to the results of the SEM analysis the average particle size of the cubic nanoparticles was seen as 26.2 nm. The catalytic properties of CuO@Pd NPs were determined by the sodium borohydride hydrolysis reaction. As a result of catalyst, substrate, temperature, and reusability experiments, some activation parameters required for a catalytic reaction of nanoparticles were calculated. The activation energy of CuO@Pd NPs was calculated as 37.39 kJ/mol, enthalpy change as 34.84 kJ/mol, and entropy change as -189.8 J/mol.K. TOF, which is an indicator of hydrogen efficiency, was calculated as 1513.4 h-1. Reusability experiments were carried out in 4 cycles and the catalytic activity of CuO@Pd NPs was measured as 70 %. In light of these results, it was seen that nanoparticles provide optimal conditions for a catalytic reaction.