Influence of vacuum pre-sintering temperature on the Eu2+-Dy3+ co-doped SrAl2O4 ceramics with persistent luminescence

(Sr0.97Eu0.01Dy0.02)Al2O4 persistent luminescence (PersL) ceramics were fabricated by solid-state reactive pre-sintering in vacuum combined with hot isostatic pressing (HIP) post-treatment adding H3BO3 as a sintering additive. The influence of pre-sintering temperature on the phase composition, microstructure, and PersL performance of (Sr0.97Eu0.01Dy0.02)Al2O4 ceramics was investigated. The results showed that optimum persistent performance was obtained by the ceramics prepared by vacuum pre-sintered at 1600 degrees C for 3 h and HIP post-treated at 1400 degrees C for 3 h under 200 MPa in Ar. The persistent initial luminescence intensity exceeded 9200 mcd/m(2) after 5 min when the optimum sample was simulated by the daylight irradiation of 1000 lx, and the persistent emission decay time was longer than 14 h. The trap depth was calculated using two methods, and the results showed that the ceramics prepared at pre-sintering temperature of 1600 degrees C had the highest trap depth.