Influence of energy transfer from Ce~(+3) to Eu~(2+) on luminescence properties of CaSi_2O_2N_2:Ce~(3+), Eu~(2+) phosphors

摘要

CaSi_2O_2N_2 phosphors co-doped with Ce~(3+) and Eu~(2+) was synthesized via solid-state reaction method. The experiments aimed at optimizing the composition of those phosphors for achieving the highest luminescence intensity as well as at shedding light in the mechanism that governs their luminescence behavior. The overlap of the blue emission spectrum due to Ce~(3+) with the yellow excitation spectrum due to Eu~(2+) suggests resonance-type energy transfer mechanism from Ce~(3+) to Eu~(3+) taking place in the CaSi_2O_2N_2 host lattice, where electric dipole-dipole interactions dominate. The properties of the produced phosphors qualify them for further consideration in the technology of white light-emitting diodes.