Samarium doped apatite-type orange-red emitting phosphor Ca5(PO4)2SiO4 with satisfactory thermal properties for n-UV w-LEDs

A novel single-phase Smactivated Ca(PO)SiOphosphor was successfully fabricated via a conventional solid-state method, which can be e fficie ntly excited by near ultraviolet(n-UV) light-emitting chips.The crystal structure and luminescence properties were characterized and analyzed systematically by using relevant instruments. The Ca(PO)SiO:Smphosphor shows an orange-red emission peaking at600 nm under the excitation of 403 nm and the optimal doping concentration of Smis determined to be 0.08, The critical distance of Ca(PO)SiO:0.08 Smis calculated to be 1.849 nm and concentration quenching mechanism of the Smin Ca(PO)SiOhost is ascribed to energy transfer between nearestneighbor activators. The decay time of Ca(PO)SiO: 0,08 Smis determined to be 1.1957 ms. In addition, the effect of temperature on the emission intensity was also studied, 72.4% of the initial intensity is still preserved at 250 ℃, better thermal stability compared to commercial phosphor YAG:Ceindicates that Ca(PO)SiO:0.08 Sm3+ has excellent thermal stability and active energy is deduced to be 0.130 eV.All the results demonstrate that orange-red emitting Ca(PO)SiO:0.08 Smphosphor exhibits good luminescent properties. Owing to the excellent thermal quenching luminescence property,Ca(PO4)SiO:0.08 Smphosphor can be applied in n-UV white light emitting diodes and serve as the warm part of white light.