Preparation of CaAl2O4: Eu2+ Long Persistent Blue Phosphor

Abstract

CaAl2O4:Eu2+ with high brightness and long persistent luminescence were prepared by solid state reaction method. The phosphor compositions with varying Eu2+ were investigated by powder X-ray diffractometer (XRD), SEM, TEM, photoluminescence excitation and emission spectra. Broad band UV excited luminescence of the CaAl2O4:Eu2+ was observed in the blue region (λmax = 440 nm) due to transitions from the 4f65d1 to the 4f7 configuration of the Eu2+ ion. The particle size also plays a role deciding the luminescence characteristics of these phosphors. The decay time of the persistence indicated that the persistent luminescence phosphor has bright phosphorescence and maintains a long duration.