Color tunable emission in Ce3+ and Tb3+ co-doped Ba2Ln(BO3)2Cl (Ln = Gd and Y) phosphors for white light-emitting diodes

Ce3+ and Tb3+ co-doped Ba(2)Ln(BO3)(2)Cl (Ln = Y and Gd) green emitting phosphors were prepared by solid state reaction in reductive atmosphere. The emission and excitation spectra as well as luminescence decays were investigated, showing the occurrence of efficient energy transfer from Ce3+ to Tb3+ in this system. The phosphors exhibit both a blue emission from Ce3+ and a green emission from Tb3+ under near ultraviolet light excitation with 325-375 nm wavelength. Emission colors of phosphors could be tuned from deep blue through cyan to green by adjusting the Tb3+ concentrations. The energy transfer efficiency and emission intensity of Ba2Y(BO3)(2)CI:Ce3+, Tb3+ precede those of Ba2Gd(BO3)(2)Cl:Ce3+, Tb3+, and the sample Ba2Y(BO3)(2)Cl:0.03Ce(3+), 0.10Tb(3+) is the best candidate for n-UV LEDs. (C) 2013 Elsevier B.V. All rights reserved.