Enhancing the photoluminescence performance of Ca5(PO4)2SiO4:Re3+ (Re = Eu, Sm) phosphors with A3+ (A = La, Bi) codoping and white light-emitting diode application

The Ca 5 (PO 4 ) 2 SiO 4 :Eu 3+ and Ca 5 (PO 4 ) 2 SiO 4 :Sm 3+ phosphors were obtained via solid-state reaction, and A 3+ (A = La, Bi) ions were further co-doped in the host for luminescence enhancement. The XRD results showed that the samples have a Ca 5 (PO 4 ) 2 SiO 4 structure with good crystallinity. The characteristic peaks of Ca 5 (PO 4 ) 2 SiO 4 :Eu 3+ , A 3+ and Ca 5 (PO 4 ) 2 SiO 4 :Sm 3+ , A 3+ phosphors severely appeared at 616 nm and 605 nm, which is originating from the 4f-4f transitions of Eu 3+ and Sm 3+ ions. Compared with Ca 4.8 (PO 4 ) 2 SiO 4 :0.2Eu 3+ , the luminescence intensity of Ca 4.8- y (PO 4 ) 2 SiO 4 :0.2Eu 3+ , y A 3+ was increased by 1.34- and 1.65-fold with La 3+ /Bi 3+ co-doping, respectively. And the luminescence intensity reached 1.77- and 1.49-fold that of Ca 4.9 (PO 4 ) 2 SiO 4 :0.1Sm 3+ for Ca 4.9- y (PO 4 ) 2 SiO 4 :0.1Sm 3+ , y A 3+ , Meanwhile, Ca 4.7 (PO 4 ) 2 SiO 4 :0.2Eu 3+ , 0.1Bi 3+ and Ca 4.75 (PO 4 ) 2 SiO 4 :0.1Sm 3+ , 0.15La 3+ phosphors had excellent thermal stability and the luminescence intensity at 210 °C still maintained at 75.16% and 93.02% of that at room temperature. In addition, some w -LEDs were manufactured via mixing the as-prepared phosphor with others, which exhibited a white light with excellent chromaticity parameters (CCT = 4726 K, Ra = 89.3). All results manifested that the excellent Ca 5 (PO 4 ) 2 SiO 4 :Eu 3+ , Bi 3+ phosphor was expected to be used as a red component in solid-state lighting devices.