Enhanced luminescence intensity of novel red-emitting phosphor -Sr3Lu2(BO3)4:Bi3+,Eu3+ via energy transfer

Abstract

Bi 3+ /Eu 3+ co-activated Sr 3 Lu 2 (BO 3 ) 4 was successfully synthesized via a solid state reaction. The optimal concentration of Bi 3+ ,Eu 3+ and Bi 3+ /Eu 3+ are 1 mol%, 60 mol% and 1 mol%/20 mol%, respectively. The emission spectra of Sr 3 Lu 2 (BO 3 ) 4 :Bi 3+ , Eu 3+ gives three peaks located at 405 nm, 489 nm which were attributed to Bi 3+ S 6 (blue) and C 2 (green) site symmetry, respectively and 610 nm which was ascribed to Eu 3+ ( 5 D 0 → 7 F 2 ) transition. The emission intensity of Bi 3+ decreases with increasing Eu 3+ content which indicates that a efficient energy transfer occurred in the Sr 3 Lu 2 (BO 3 ) 4 host. The relative intensity of Sr 3 Lu 1.79 (BO 3 ) 4 :0.01Bi 3+ ,0.20Eu 3+ excited at 327 nm and 370 nm was remarkably enhanced by 201% and 265%, respectively, via the energy transfer from Bi 3+ to Eu 3+ . The results indicate that Sr 3 Lu 2 (BO 3 ) 4 :Bi 3+ , Eu 3+ is a potential novel red-emitting phosphor for UV LED applications.