铕钐离子双掺磷酸钇钙白色荧光粉的合成及发光性能

Synthesis and Photoluminescence Properties of Single-Phased White-Light-Emitting Ca_3Y(PO_4)_3:Eu^(2+)/Sm^(3+) Phosphor

利用高温固相法合成了一种颜色可调的Ca_3Y(PO_4)_3:Eu^(2+)/Sm^(3+)白色荧光粉。X射线衍射图谱证明了掺入Eu^(2+)和Sm^(3+)离子的样品为纯相Ca_3Y(PO_4)_3样品。分析漫反射光谱,样品在250~450nm范围内有较强的吸收,即该荧光粉适用于紫外LED芯片。发射光谱证明,在405nm激发波长下,Eu^(2+)和Sm^(3+)离子被共激发。调节Eu^(2+)和Sm^(3+)离子的掺杂量,其色坐标从蓝绿光区域进入白光区域,最终落在橙红光区域。通过麦卡米经验公式计算该白色荧光粉的相对色温(其色温值为5 058K),进一步证明此荧光粉在室内照明也有着良好的应用前景。研究双掺样品Eu^(2+)离子的荧光寿命也证明了Eu^(2+)与Sm^(3+)之间存在着能量传递,其作用机理主要为电偶极-电偶极相互作用。

A single-phased color-tunable phosphor Ca 3Y(PO 4)3:Eu 2+/Sm 3+for WLED was prepared by a conventional solid-state reaction method.X-ray diffraction confirms that the as-prepared samples were single phase Ca 3Y(PO 4)3 phosphors.The obtained phosphors exhibit a strong excitation band between 250 and 450 nm,matching well with the dominant emission band of UV light-emitting-diode(LED)chip.In order to tune the emitting color of Ca 3Y(PO 4)3:Eu 2+phosphor,Sm 3+ions were co-doped in.Under 405 nm excitation,Eu 2+and Sm 3+ions are co-activated so as to produce white light.Meanwhile,the emitting color can be tuned from blue-green to white and eventually to orange-red by precisely controlling the ratio of Eu 2+to Sm 3+.A correlated color temperature(5 058 K)of the sample with white region was calculated,which shows its suitable application for indoor lighting also.Moreover,we also certify the existence of energy transfer from Eu 2+to Sm 3+via electric dipole-dipole interaction.