Structure and luminescence properties of color-tunable phosphor Sr2La3(SiO4)3F:Tb3+,Sm3+

A series of single-phase and color-tunable phosphors Sr2La3(SiO4)3F:0.15Tb3+,xSm3+ (SLSOF:0.15Tb3+,xSm3+) was prepared using solid-state route. The X-ray diffraction (XRD) was used to characterize the phase of the as-prepared samples. The synthesized phosphors have apatite-type structure without other impurities. Sm3+ and Tb3+ ions substitute La3+ into the lattice and form a single-phase solid solution. The elements are evenly distributed in the sample according to the scanning electron microscopy (SEM) results. The crystal structure of the host phosphor was refined by the Rietveld method. The optical properties were studied in detail by investigation of the luminescence and diffuse spectra, fluorescence decay curves and energy transfer efficiency. The phosphor color can be changed from green (0.29, 0.48) to yellow/orange and red (0.57, 0.42) via adjusting the doping ratio of Sm3+. The SLSOF:0.15Tb3+,xSm3+ phosphors can emit typical multicolor light such as green, yellow, orange and red with gradually increasing Sm3+ doping concentration. All results indicate the occurrence of the energy transfer which results in the color-tunable properties of the phosphors.