Synthesis of long afterglow SrAl2O4:: EU2+, Dy3+ phosphors through microwave route

A novel and fast microwave route is used for the synthesis of SrAl2O4:Eu2+, Dy3+ powder phosphors. Based on the XRD peaks, the powder phosphors were identified as SrAl2O4 phase, which is monoclinic (a = 8.4424Angstrom, b = 8.822 Angstrom, c = 5.1607Angstrom, beta = 93.415degrees). Compared with those synthesized by solid-state reaction process, the phosphors show a smaller grain size (about 4.8 mum). It exhibited broadband peaks in both the excitation and emission spectra. A clear blue shift occurs in the excitation and emission spectra of these phosphors compared to those synthesized by solid-state reaction process. The excitation peaks lied between 300 nm and 450 nm, and the main emission peaks lied around 507 nm. The afterglow curve shows that the initial luminescent intensity of the phosphors synthesized through microwave route decreases greatly.