Volume 3 Issue 1
Authors: Eman H. Ismail; Mostafa M.H. Khalil; Fozia A. Al Seif; Fatma El-Magdoub
Abstract: A novel synthesis gold nanoparticles (GNPs) using a water extract of grape leaves and seeds as a natural source of both a reducing and stabilizing agents were reported. The gold nanoparticles obtained were characterized by UV–visible spectra, transmission electron microscopy (TEM) and X-ray diffraction (XRD). TEM studies showed the particles to be of various shapes and sizes. The XRD patterns of the GNPs showed a (1 1 1) preferential orientation of the gold nanoparticles. Fourier transform infra-red spectroscopy (FTIR) measurements showed the GNPs having a coating of the extract compounds indicating a possible role of phenolic groups for capping and stabilization of the gold nanoparticles. The photoluminescence measurements revealed the oxidation of the extract compounds during the process of Au3+ reduction. As we used green and eco-friendly synthetic reagents used in this method, the gold nanoparticles could have potential for application in bio-molecular imaging and therapy.
Keywords: Gold Nanoparticles; Grape Leaves; Grape Seeds Extract; Antioxidant
Synthesis XRD TEM and Optical Absorption Spectroscopic Characterization of Copper Doped Nano Apatite
Authors: G. Udayabashakar Reddy; T. Ravindra Reddy; K. Suvarna Padmalatha; S. Lakshmi Reddy; Hiroaki Nishikawa; Tamio Endo
Abstract: Synthesized copper doped chloro-apatite has been characterized by XRD, TEM, Optical and NIR spectroscopy. XRD pattern indicates that the compound shows hexagonal structure with lattice constants of a = b = 9.027 Å and c = 13.767 Å. TEM images suggest that nano crystals are closely joined together and form agglomerates with rod in shape and are parallel. The optical spectrum exhibits a number of electronic bands due to presence of Cu(II) ions in the compound. The bands in NIR spectra are due to the overtones and combinations of water and phosphate molecules.
Keywords: Copper Doped Chloro-Apatite; XRD; TEM; Optical Absorption; NIR Spectroscopy
Authors: C. Amutha; B. Lawrence; K. Kulathuraan; V. Ramadas; B. Natarajan; A. Dhanalakshmi
Abstract: Zinc Oxide thin films (ZnO) were deposited successfully on glass substrate by sol-gel dip coating method by varying precursor concentrations. The structural properties of ZnO thin films were investigated by X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) techniques. The optical properties of ZnO thin films were also characterised using UV visible Spectrophotometer, Fourier Transform Infrared Spectrometer (FTIR) and Photoluminescence (PL) studies. The XRD analysis of all ZnO films showed hexagonal structure with c-axis orientation along (002) plane, whereas SEM image of ZnO thin films showed granular surface. The UV visible spectral study showed a higher transmittance in the visible region with a direct band gap value in the range of 3.2 eV to 3.3 eV for prepared Zinc Oxide thin films. FTIR spectra indicated a ZnO stretching mode at 480 cm-1. The PL spectra of ZnO sample gave an intense visible strongest ultraviolet emission peak centred at 380 nm and weak blue emission peak around 480 nm.
Keywords: ZnO; Sol-gel Method; XRD; SEM; Optical; FTIR