A red-emitting phosphor for white LEDs and its luminescence properties

A batch of phosphors In-1.6(WO4)(x)(MoO4)(3-x):0.4Eu(3+) (x=0.02, 0.04, 0.06, 0.08, 0.10) were synthesized by a solid-state method in high temperature air. The crystallization and luminescence properties were respectively identified by X-ray diffraction (XRD) and molecular fluorescence spectrometer. The XRD pattern shows that the phosphor has no impure phase. The excitation spectrum demonstrates that the phosphor can be efficiently excited by near UV light at 394 nm and blue light at 465 nm. The emission spectrum presents the phosphor exhibiting bright red emission at 611 nm due to the Eu3+ transition of D-5(0) -> F-7(2). WO42- content does not make the emission shapes and peak positions change except for the emission intensity. When x is equal to 0.04, the intensity reaches the maximum. The color coordinates are x=0.60 and y=0.36, which are close the standard red values (0.67,0.33). The results indicates that the In-1.6(WO4)(0.04)(MoO4)(2.96):0.4Eu(3+) may be a promising red-emitting phosphor for white LEDs.