Synthesis characterization and luminescence studies of gamma irradiated nanocrystalline yttrium oxide

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2016-02, Vol.154, p.220-231
• Main Authors: Shivaramu, N.J., Lakshminarasappa, B.N., Nagabhushana, K.R., Singh, Fouran
• Format: Article
• Language: English
• Subjects: Combustion synthesis; Electron spin resonance; FE-SEM; Photoluminescence; Radiation effects; Thermoluminescence
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2015.09.019

Nanocrystalline Y2O3 is synthesized by solution combustion technique using urea and glycine as fuels. X-ray diffraction (XRD) pattern of as prepared sample shows amorphous nature while annealed samples show cubic nature. The average crystallite size is calculated using Scherrer's formula and is found to be in the range 14–30nm for samples synthesized using urea and 15–20nm for samples synthesized using glycine respectively. Field emission scanning electron microscopy (FE-SEM) image of 1173K annealed Y2O3 samples show well separated spherical shape particles and the average particle size is found to be in the range 28–35nm. Fourier transformed infrared (FTIR) and Raman spectroscopy reveals a stretching of Y–O bond. Electron spin resonance (ESR) shows V− center, O2− and Y2+ defects. A broad photoluminescence (PL) emission with peak at ~386nm is observed when the sample is excited with 252nm. Thermoluminescence (TL) properties of γ-irradiated Y2O3 nanopowder are studied at a heating rate of 5Ks−1. The samples prepared by using urea show a prominent and well resolved peak at ~383K and a weak one at ~570K. It is also found that TL glow peak intensity (Im1) at ~383K increases with increase in γ-dose up to ~6.0kGy and then decreases with increase in dose. However, glycine used Y2O3 shows a prominent TL glow with peaks at 396K and 590K. Among the fuels, urea used Y2O3 shows simple and well resolved TL glows. This might be due to fuel and hence particle size effect. The kinetic parameters are calculated by Chen's glow curve peak shape method and results are discussed in detail. PL spectra (λex=252nm) of pristine and 6.0kGy γ-irradiated U:Y2O3 and G:Y2O3. [Display omitted] •This paper discusses the gamma induced and fuel effects on PL and TL properties.•Electron spin resonance shows oxygen vacancy related defects and O2− coordinated to Y3+.•A broad PL emission with peak at 386nm is observed.•Annealed at 1173K sample shows high PL and TL intensity.•U:Y2O3 sample shows high sensitivity, linear TL response and less fading.