Effect of Al/Ga substitution on photoluminescence and chromatic properties of Y3Al5−xGaxO12:Ce3+ phosphor

Y 3 Al 5−x Ga x O 12 :0.05Ce 3+ (x = 0–2) phosphors have been prepared by using the high temperature solid state reaction in a reducing H 2 atmosphere. The phase structures, photoluminescence (PL) properties, and chromaticity properties of the phosphors have been investigated in detail. SEM image shows the phosphors exhibits well-developed crystal faces with the crystal size is about 50 μm. The two PLE excitation bands attributed to the 4 f –5 d 1 and 4 f –5 d 2 transitions showed shift in opposite directions as x increasing. PL emission bands of Y 3 Al 5−x Ga x O 12 :0.05Ce 3+ showed a blue-shift tendency gradually from 560 to 520 nm with increasing Ga content (x value). The PL measurement combined with blue light and CIE chromaticity diagram show that ideal white light with high CRI can be obtained by mixing the Y 2.95 Al 3.5 Ga 1.5 O 12 :0.05Ce (or Y 2.95 Al 3 Ga 2 O 12 :0.05Ce) phosphors and commercial red phosphors with appropriate proportion of the components.