Color-tunable LaCaAl3O7:Ce3+,Tb3+ phosphors for UV light-emitting diodes

Color tunable LaCaAl3O7:0.05Ce(3+),yTb(3+) (LCA:0.05Ce(3+),yTb(3+)) phosphors were synthesized by solid state reaction. The luminescence spectra and the lifetime were investigated in detail. Results confirm that Tb3+ can substitute all La3+ sites without impure phase, and cause luminescence spectra shifting to longer wavelength. Besides, an efficient energy transfer with efficiency over 80% from Ce3+ to Tb3+ was found in the LCA host. Through this efficient energy transfer process, the hues of obtained phosphors changed from blue-white to green light. The results demonstrate its potential of applying in white light-emitting diodes. (C) 2012 Elsevier Ltd. All rights reserved.