Tunable color emission in K3Gd(PO4)2:Tb3+,Sm3+ phosphor for n-UV white light emitting diodes

Abstract A series of K 3 Gd(PO 4 ) 2 :Tb 3+ ,Sm 3+ phosphors were synthesized through solid state reaction. By co-doping Tb 3+ and Sm 3+ into K 3 Gd(PO 4 ) 2 host and singly varying the doping concentration of Sm 3+ , tunable colors from green to yellow and then to orange were obtained in K 3 Gd(PO 4 ) 2 :Tb 3+ ,Sm 3+ phosphors under the excitation at 373 nm. The energy transfer process from Tb 3+ to Sm 3+ was verified through luminescence spectra and fluorescence decay curves. Moreover, the energy transfer mechanism was demonstrated to be the quadrupole-quadrupole interaction. The results indicated that K 3 Gd(PO 4 ) 2 :Tb 3+ ,Sm 3+ phosphors could be a potential application for n-UV white light emitting diodes.