Photoluminescence properties of Sm3+-doped LiY(MoO4)2 red phosphors

A series of novel Sm3+-doped LiY(MoO4)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(MoO4)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 (6H5/2→4D3/2), 378 nm (6H5/2→6P7/2), 406 nm (6H5/2→4F7/2), 420 nm (6H5/2→6P5/2), 442 nm (6H5/2→4G9/2), 471 nm (6H5/2→4I13/2) and 482 nm (6H5/2→4I9/2), respectively. The strongest emission was excited by 406 nm, and the main emissions were located at 568 nm (4G5/2→6H5/2), 610 nm (4G5/2→6H7/2), 649 nm (4G5/2→6H9/2) and 710 nm (4G5/2→6H11/2). Photoluminescence properties were determined for various concentrations of Sm3+-doped LiY(MoO4)2 host, and the luminescence intensity had the best value when x=0.02 in LiY1−x(MoO4)2:xSm3+.