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A series of novel Sm 3+ -doped LiY(MoO 4 ) 2 red phosphors under the UV excitation were synthesized by solid state reaction at 800 °C for 7 h. The data measured by X-ray diffraction (XRD) indicated that the samples were all pure phases of LiY(MoO 4 ) 2 . Their excitation spectra had a broad band ranging from 250 to 350 nm and several sharp peaks. The centers of the peaks were located at about 365 nm ( 6 H 5/2 → 4 D 3/2 ), 378 nm ( 6 H 5/2 → 6 P 7/2 ), 406 nm ( 6 H 5/2 → 4 F 7/2 ), 420 nm ( 6 H 5/2 → 6 P 5/2 ), 442 nm ( 6 H 5/2 → 4 G 9/2 ), 471 nm ( 6 H 5/2 → 4 I 13/2 ) and 482 nm ( 6 H 5/2 → 4 I 9/2 ), respectively. The strongest emission was excited by 406 nm, and the main emissions were located at 568 nm ( 4 G 5/2 → 6 H 5/2 ), 610 nm ( 4 G 5/2 → 6 H 7/2 ), 649 nm ( 4 G 5/2 → 6 H 9/2 ) and 710 nm ( 4 G 5/2 → 6 H 11/2 ). Photoluminescence properties were determined for various concentrations of Sm 3+ -doped LiY(MoO 4 ) 2 host, and the luminescence intensity had the best value when x =0.02 in LiY 1− x (MoO 4 ) 2 : x Sm 3+ . |
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