摘要
A novel series of color-tunable single-phased phosphors La1-x-yPO4：xEu3＋/yTb3＋（x=0, 0.01, 0.02, 0.03, 0.04, 0.05; y=0, 0.05, 0.10, 0.15, 0.20） was synthesized via microwave-assisted co-precipitation method with diammonium hydrogen phosphate as precipitant. The morphology, crystal structure and photoluminescence properties of the as-prepared samples were characterized by means of X-ray diffraction（XRD）, scanning electron microscopy（SEM） and fluorescence spectrophotometer. The results reveal that the as-synthesized samples calcined at 1100 ℃ display spherical morphology with uniform distribution. Upon excitation with 350 nm ultraviolet radiation, the LaPOa：Eu3＋/Tb3＋ phosphors showed a green light peaking at 543 nm assigned to the characteristic 5Da-7F5 emission of Tb3＋ and a red light peaking at 591 nm corresponding to the characteristic 5D0-7F1 emission of Eu3＋ simultaneously. For the Eu3＋/Tb3＋ co-activated phosphors, Tb3＋ acts as an efficient sensitizer to enhance the emission intensity of Eu3＋ ions. The energy transfer mechanism and the emission color tunability of LaPO4：Eu3＋/Tb3＋ have been studied. The results indicate that a color-tunable luminescence（from green to white to red） can be achieved by adjusting the Eu3＋/Tb3＋ doping ratio in the LaPO4 host matrix.
A novel series of color-tunable single-phased phosphors La1-x-yPO4：xEu3＋/yTb3＋（x=0, 0.01, 0.02, 0.03, 0.04, 0.05; y=0, 0.05, 0.10, 0.15, 0.20） was synthesized via microwave-assisted co-precipitation method with diammonium hydrogen phosphate as precipitant. The morphology, crystal structure and photoluminescence properties of the as-prepared samples were characterized by means of X-ray diffraction（XRD）, scanning electron microscopy（SEM） and fluorescence spectrophotometer. The results reveal that the as-synthesized samples calcined at 1100 ℃ display spherical morphology with uniform distribution. Upon excitation with 350 nm ultraviolet radiation, the LaPOa：Eu3＋/Tb3＋ phosphors showed a green light peaking at 543 nm assigned to the characteristic 5Da-7F5 emission of Tb3＋ and a red light peaking at 591 nm corresponding to the characteristic 5D0-7F1 emission of Eu3＋ simultaneously. For the Eu3＋/Tb3＋ co-activated phosphors, Tb3＋ acts as an efficient sensitizer to enhance the emission intensity of Eu3＋ ions. The energy transfer mechanism and the emission color tunability of LaPO4：Eu3＋/Tb3＋ have been studied. The results indicate that a color-tunable luminescence（from green to white to red） can be achieved by adjusting the Eu3＋/Tb3＋ doping ratio in the LaPO4 host matrix.
基金
Supported by the National Natural Science Foundation of China（No.50772016）.
