Blue-green tunable color of Ce3+/Tb3+ coactivated NaBa3La3Si6O20 phosphor via energy transfer

Abstract

A series of color tunable phosphors NaBa3La3Si6O20:Ce3+, Tb3+ were synthesized via the high-temperature solid-state method. NaBa3La3Si6O20 crystallizes in noncentrosymmetric space group Ama2 with the cell parameters of a = 14.9226(4) Å, b = 24.5215(5) Å and c = 5.6241(2) Å by the Rietveld refinement method. The Ce3+ ions doped NaBa3La3Si6O20 phosphors have a strong absorption band from 260 to 360 nm and show near ultraviolet emission light centered at 378 nm. The Ce3+ and Tb3+ ions coactivated phosphors exhibit color tunable emission light from deep blue to green by adjusting the concentration of the Tb3+ ions. An energy transfer of Ce3+ → Tb3+ investigated by the photoluminescence properties and lifetime decay, is demonstrated to be dipole-quadrupole interaction. These results indicate the NaBa3La3Si6O20:Ce3+, Tb3+ phosphors can be considered as potential candidates for blue-green components for white light emitting diodes.