Enhanced luminescence of Dy3+ in Y3Al5O12 by Bi3+ co-doping

In the present paper, phosphors with the composition Y3−x−yAl5O12:Bi3+x, Dy3+y were synthesized with solid state reactions. The luminescence properties of Bi3+ and Dy3+ in Y3Al5O12(YAG) and the energy transfer from Bi3+ to Dy3+ were investigated in detail. Bi3+ in YAG emits one broad band peaking at 304 nm which can be ascribed to the transition from excited states 3P0, 1 to ground state 1S0. Dy3+ in YAG emits two groups of peaks around 484 and 583 nm, respectively, which can be ascribed to the transitions from excited state 4F9/2 to ground states 6H15/2 and 6H13/2. The co-doping of Bi3+ enhances the luminescent intensity of Dy3+ by ∼7 times because Bi3+ can transfer the absorbed energy to Dy3+ efficiently. The mechanism of energy transfer was also discussed.