“…In addition to the silicate-based (Sr, Ca) 2 (Mg, Zn)Si 2 O 7 [10][11][12], the Ln doped silicate-aluminate based phosphors are also studied as long afterglow materials. Ding et al [13] have reported the Eu/Dy codoped Sr 2 Al 2 SiO 7 . The phosphor shows a broad emission band peaking at 484 nm and a long afterglow is observed.…”