Luminescence studies of rare earth doped yttrium gadolinium mixed oxide phosphor

Abstract

This paper reports the photoluminescence and thermoluminescence properties of gamma ray induced rare earth doped yttrium gadolinium mixed oxide phosphor. The europium (Eu 3 þ ) was used as rare earth dopant. The phosphor was prepared by chemical co-precipitation method according to the formula (Y2 � xyGdx )O 3 :E u y 3 þ (x¼ 0.5; y¼ 0.05). The photoluminescence emission spectrum of the prepared phosphor shows intense peaks in the red region at 615 nm for 5 D0- 7 F2 transitions and the photoluminescence excitation spectra show a broad band located around 220-270 nm for the emission wavelength fixed at 615 nm. The thermoluminescence studies were carried out after irradiating the phosphor by gamma rays in the dose range from 100 Gy to 1 KGy. In the thermo- luminescence glow curves, one single peak was observed at about 300 1C of which the intensity increases linearly in the studied dose range of gamma rays. The glow peak was deconvoluted by GlowFit program and the kinetic parameters associated with the deconvoluted peaks were calculated. The kinetic parameters were also calculated by various glow curve shape and heating rate methods. & 2012 Elsevier B.V. All rights reserved.