Effects of Li+Codoping on the Optical Properties of SrAl2O4Long Afterglow Ceramic Phosphors

摘要

Rare-earths codoped long afterglow strontium aluminate phosphors with high brightness were synthesized via a facile combustion synthesis method using urea as a fuel. The resulted phosphor particles were analyzed by using X-ray diffraction and field emission scanning electron microscope, whereas their optical properties were monitored by photoluminescence spectroscopy. The prepared SrAl2O4:Eu2+, Dy3+, Li+samples showed a broad green-yellowish emission, peaking at 512 nm when excited by 348 nm. Compared to traditional SrAl2O4:Eu2+, Dy3+phosphor, the initial luminescence brightness of SrAl2O4:Eu2+, Dy3+, codoped with Li+improved from 1.89 cd/m2to 2.71 cd/m2and the afterglow decay time was prolonged from 103 to 121 min. The possible mechanism of SrAl2O4:Eu2+, Dy3+, Li+phosphorescence enhancement has been discussed.