Energy transfer and color-tunable emission in Ba2Y2Si4O13:Bi3+,Eu3+ phosphors

Single-composition Ba 2 Y 2 Si 4 O 13 :Bi 3+ ,Eu 3+ (BYSO:Bi 3+ ,Eu 3+ ) phosphors with color-tunable and white emission were prepared by conventional high temperature solid-state reaction method. The structural and luminescent properties of these phosphors were thoroughly investigated through X-ray diffraction, photoluminescence, and decay curves. BYSO:Bi 3+ phosphors show two excitation peaks at 342 and 373 nm, and give two emission peaks at 414 and 503 nm, respectively, indicating that there are two sites of Bi 3+ in BYSO. The energy transfer from Bi 3+ to Eu 3+ was investigated in detail. Varied hues from blue (chromaticity coordinate [0.219, 0.350]) to white (0.288, 0.350) and orange-red light (0.644, 0.341) can be generated by adjusting the content of Eu 3+ . Pure white light emission (0.311, 0.338) can be obtained under the excitation of 355 nm in BYSO:3%Bi 3+ ,20%Eu 3+ phosphor. Besides, BYSO:Bi 3+ ,Eu 3+ phosphors exhibit distinct thermal quenching properties, whose emission intensity at 473 K is 82.6% of that at 298 K. Our results indicate that BYSO:Bi 3+ ,Eu 3+ may be applied as conversion phosphors for n-UV-based W-LEDs.