Synthesis and Luminescence Properties of Li4SrCa(SiO4)(2):Eu3+ Red Phosphor

Li4SrCa(SiO4)(2):Eu3+ red phosphor was synthesized by a high-temperature solid-phase method using silicate as a host material. The phase, morphology, and luminescence properties of the powder were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and fluorescence spectroscopy. The results showed that the crystal structure does not change after the addition of the europium ion. Under the light excitation at 393 nm, the emission peak intensity of the sample was the strongest at 693 nm. With 693 nm as the monitoring wavelength, the main excitation peaks were 361 nm (F-7(0) -> D-5(4)), 375 nm (F-7(0) -> (5)G(3)), 413 nm (F-7(0) -> D-5(3)), 393 nm (F-7(0) -> L-5(6)), and 464 nm (F-7(0) -> D-5(2)), which suggests that the phosphor has good absorption to near-ultraviolet and blue light, and has the potential to produce white light-emitting diodes. The effect of Eu3+ doped concentration on the luminescence intensity of phosphor was studied by emission spectroscopy. When the doped concentration of europium ion (molar fraction, x) was equal to 0.10, the emission intensity of the sample was the strongest, and the sample emitted red light. The mechanism of concentration quenching was analyzed by the relationship between Dexter strength and concentration.