Abstract
V2O5 nanowires (NWs) were grown on Si (100) and quartz substrates using evaporation-condensation method with the VLS growth technique. The chemical composition of the synthesized nanostructures was analyzed using energy dispersive analysis of X-ray (EDAX). The surface morphology and crystal structure of the synthesized NWs were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD), respectively. The XRD pattern revealed an orthorhombic symmetry of the deposited NWs while the SEM showed randomly distributed NWs with diameters of 50-200 nm and lengths in the range of 0.8-1.5 mu m. The spectroscopic ellipsometry data for V2O5 NWs films were acquired in the wavelength range 400-2100 nm. The thickness and optical constants were obtained from the data fits. The estimated refractive index for V2O5 NWs was found to be 2.24 at lambda=626.30 nm. The indirect and direct band gap values were calculated and found to be 2.26 +/- 0.02 eV and 2.83 +/- 0.02 eV, respectively. The Urbach energy E-u value was 286 meV. (C) 2013 Elsevier Ltd. All rights reserved.