abstract
A series of YAB:Eu3+/Tb3+ co-activated phosphors of composition Y(1-x-y)Al3(BO3)(4)xEu(3+)/yTb(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. Eu3+/Tb3+ co-doped phosphors have shown their excellent luminescent properties in their respective emission regions. The YAB:2%Eu3+ 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 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 F-7(0)-> D-5(3,2,1,0) (Eu3+); F-7(1)->>D-5(1,0)(Eu3+); F-7(2)-> D-5(1)(Eu3+) excitation and D-5(3)-> F-7(5,4,3) (Tb3+); D-5(4)-> F-7(5,4)(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. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
keywords
RARE-EARTH IONS; LIGHT-EMITTING-DIODES; LANTHANIDE AQUO IONS; THIN-FILMS; SPECTROSCOPIC PROPERTIES; LUMINESCENT PROPERTIES; TB; EU; PHOTOLUMINESCENCE; NANOPHOSPHORS
subject category
Materials Science
authors
Reddy, GVL; Moorthy, LR; Chengaiah, T; Jamalaiah, BC
our authors
Bungala Chinna Jamalaiah
Post-doc FellowshipGroups
acknowledgements
One of the authors Dr. B.C. Jamalaiah would like to thank the Fundacao para a Ciencia e a Tecnologia (FCT), Ministerio da Educacao e Ciencia, PORTUGAL for supporting him as a Post-Doctoral Researcher wide Ref. no. SFRH/BPD/76581/2011.