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

Abstract

A series of YAB:Eu3+/Tb3+ co-activated phosphors of composition Y(1−x−y)Al3(BO3)4:xEu3+/yTb3+ (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. Eu3+/Tb3+ co-doped phosphors have shown their excellent luminescent properties in their respective emission regions. The YAB:2%Eu3+ phosphor under 395nm 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 Y2O3:Eu3+ red phosphor chromaticity coordinates. The emission color of Eu3+/Tb3+ co-doped phosphors has been tuned from pale-green to white as a function of Eu3+/Tb3+ concentration. Moreover, the Tb3+ acts as an efficient sensitizer and enhances the luminescence of Eu3+ by transferring absorbed excitation energy. The overlapping 7F0→5D3,2,1,0(Eu3+); 7F1→5D1,0(Eu3+); 7F2→5D1(Eu3+) excitation and 5D3→7F5,4,3 (Tb3+); 5D4→7F5,4(Tb3+) emission transitions revealed the transfer of energy from Tb3+ to Eu3+ through exchange interaction mechanism in Eu3+–Tb3+ clusters instead of from these ions randomly distributed in YAB lattice. The YAB:Eu3+/Tb3+ phosphors have potential in the field of display technology.