Synthesis and optical properties of Er and Eu 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 ⁹⁰Sr-⁹⁰Y beta source, or UV light at 311 nm, and in detail the TL signals differ somewhat between Er and Eu dopants.