The effect of annealing temperature on the structure and optical properties of well-aligned 1D SnO2 nanowires synthesized using template-assisted deposition

Abstract

We report the observation of structural characterization and optical properties in SnO2 nanowires post-treated under different annealing temperatures (300, 400, 500 & 600 oC) for 1 h. Well-aligned SnO2 nanowires with diameter of about 100-120 nm were deposited into alumina templates by means of liquid phase deposition method. The X-ray diffraction (XRD) and Raman patterns of the prepared samples were indexed to rutile phase of SnO2 without any trace of an extra phase which, was further confirmed by transmission electron microscopy (TEM). The effect of annealing temperature on the optical properties of SnO2 nanowires was studied by using UV-Vis and luminescence spectra data. The UV-Vis spectra indicated that the absorption edge is blue shifted as the annealing temperature raises and the band gap was determined to be 3.32 eV to 3.88 eV. Photoluminescence measurements showed a broad dominant emission peak in the visible region around 450-650 nm. It suggested that the visible emission can be originated from defect-related states, particularly oxygen vacancies induced during the formation of SnO2 nanowires