Photoluminescence Properties of Ca4La6(SiO4)4(PO4)2O2-based Phosphors for Wleds

The apatite compound Ca4La6(SiO4)(4)(PO4)(2)O-2 (CLSPO) was explored as the host material for phosphors used in white light-emitting diodes (wLEDs). The crystal structure of the CLSPO host prepared by the solid-state reaction method was investigated with Rietveld refinement. The rare earth ions (Eu3+/Tb3+/Ce3+, Tb3+/Tb3+, Mn2+) activated CLSPO phosphors were synthesized, and their photoluminescence properties, quantum yields, as well as thermal stabilities, were studied. Under near-ultraviolet excitations, the Eu3+ and Tb3+-doped CLSPO compounds exhibited red and green emissions with high luminescence efficiencies. Besides, tunable emissions from green to orange were obtained by introducing Mn2+ ions into the Tb3+-doped CLSPO samples. The results showed that the phosphors studied may have potential applications for wLEDs.