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Eu2+ and Dy3+ codoped(Ca,Sr)7(SiO3)6Cl2 yellow phosphors were successfully synthesized by self-flux method. The structure, morphology and photoluminescence properties were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM) and photoluminescence spectra. The as-prepared phosphor showed a broad emission spectrum centered at 550 nm for Eu2+single-doped phosphor, while located at 548–544 nm for the Eu2+, Dy3+ codoped samples under excitation at 380 nm light. The emission intensity was greatly improved when Dy3+ was doped into the(Ca,Sr)7(SiO3)6Cl2:Eu2+ system. The composition-optimized sample with 3 mol.% of Dy3+ and constant 10 mol.% of Eu2+ exhibited a 220% PL enhancement compared to the phosphor with 10 mol.% Eu2+ single-doped. Meanwhile, it was found that the quantum efficiency of phosphor namely(Ca,Sr)7(SiO3)6Cl2:3 mol.% Dy3+, 10 mol.% Eu2+ could get up to 24.6%. The synthesized yellow-emitting(Ca,Sr)7(SiO3)6Cl2:Dy3+,Eu2+ is a promising candidate as high-efficiency yellow phosphor for NUV-excited white LEDs.
The structure, morphology and photoluminescence properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and The as-prepared phosphor showed a broad emission spectrum centered at 550 nm for Eu2 + single-doped phosphor, while located at 548-544 nm for the Eu2 +, Dy3 + codoped samples under excitation at 380 nm light. The emission intensity was greatly improved when Dy3 + was doped into the (Ca, Sr) 7 (SiO3) 6Cl2: Eu2 + system. The composition- optimized sample with 3 mol.% of Dy3 + and constant 10 mol.% of Eu2 + exhibited a 220% PL enhancement compared to It was found that the quantum efficiency of phosphorium (Ca, Sr) 7 (SiO3) 6Cl2: 3 mol.% Dy3 +, 10 mol.% Eu2 + could get up to 24.6%. The synthesized yellow-emitting (Ca, Sr) 7 (SiO3) 6Cl2: Dy3 +, Eu2 + is a promising candidate as high-efficiencies Efficiency yellow phosphor for NUV-excited white LEDs.