Synthesis and optical properties of Er3+ and Eu3+ doped SrAl2O4 phosphor ceramic

We report, for the first time on luminescence from a Er3+ doped SrAl2O4 phosphor. Effects of Eu3+ doping were also studied. The influence of rare-earth doping in crystal structure and its optical properties were analysed by means of X-ray diffraction (XRD), Raman scattering, optical absorption, excitation and emission (PL) spectroscopy, thermally stimulated luminescence (TSL) and scanning electron microscope (SEM). Luminescence spectra and luminescence decay curves for Er3+ transitions in the near infrared region were recorded. The PL maximum for Eu doped SrAl2O4 is obtained at 620 nm and corresponds to the orange region of the spectrum. Diffraction patterns reveal a dominant phase, characteristic of the monoclinic SrAl2O4 compound and the presence of dopants has no effect on the basic crystal structure of SrAl2O4. The shapes of the glow curves are different for each dopant irradiated with either a Sr-90-Y-90 beta source, or UV light at 311 nm, and in detail the TL signals differ somewhat between Er and Eu dopants. (C) 2011 Elsevier B.V. All rights reserved.