Multi-color emission tunability and energy transfer studies of YAl3(BO3)4:Eu3+/Tb3+ phosphors

Abstract A series of YAB:Eu 3+ /Tb 3+ co-activated phosphors of composition Y (1− x − y ) Al 3 (BO 3 ) 4: x Eu 3+ / y Tb 3+ ( x =0, 0.3, 0.5, 1, 2% and y =0.5%) were prepared by solid-state reaction method and their photoluminescence properties were characterized. Eu 3+ /Tb 3+ co-doped phosphors have shown their excellent luminescent properties in their respective emission regions. The YAB:2%Eu 3+ phosphor under 395 nm excitation exhibited red luminescence with Commission International de I'Eclairagein chromaticity coordinates ( x =0.627, y =0.334) which are close to an ideal red and commercial Y 2 O 3 :Eu 3+ red phosphor chromaticity coordinates. The emission color of Eu 3+ /Tb 3+ co-doped phosphors has been tuned from pale-green to white as a function of Eu 3+ /Tb 3+ concentration. Moreover, the Tb 3+ acts as an efficient sensitizer and enhances the luminescence of Eu 3+ by transferring absorbed excitation energy. The overlapping 7 F 0 → 5 D 3,2,1,0 (Eu 3+ ); 7 F 1 → 5 D 1,0 (Eu 3+ ); 7 F 2 → 5 D 1 (Eu 3+ ) excitation and 5 D 3 → 7 F 5,4,3 (Tb 3+ ); 5 D 4 → 7 F 5,4 (Tb 3+ ) emission transitions revealed the transfer of energy from Tb 3+ to Eu 3+ through exchange interaction mechanism in Eu 3+ –Tb 3+ clusters instead of from these ions randomly distributed in YAB lattice. The YAB:Eu 3+ /Tb 3+ phosphors have potential in the field of display technology.