The Effect of Boron on Processing and Phosphorescence Behavior of SrAl₄O₇ (SA₂) Co-doped with Eu²⁺ and Dy³⁺

Abstract

SrAl4O7 (SA2) phosphor powders were synthesized by using a modified Pechini process. Varying amounts of boron was incorporated into the SA2 lattice to investigate the effects on crystal structure and optical properties. X-ray spectra showed that boron addition enhances phase purity of the powder at a calcination temperature of 1000 °C, whereas the formation of a new S4A7 phase was induced when a calcination temperature of 1100 °C was used. The afterglow duration was extended to longer than 5 hours when boron was present in 4-11 mol%. To elucidate the enhanced optical properties, interband trap characteristics were studied by thermoluminescence and photoluminescence.

Eu2+luminescence in strontium aluminates

“…The emission corresponds to the allowed electric-dipole transition 4f 6 5d -4f 7 of Eu 2+ . The SrAl 4 O 7 :Eu 2+ phosphor emits at longer wavelength [34][35][36] in comparison to the more ionic SrAl 12 O 19 :Eu 2+ .…”