Mei Lefu, Liu Haikun, Liao Libing, Zhang Yuanyuan, Kumar R Vasant
Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing, 100083, China.
Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, UK.
Sci Rep. 2017 Nov 9;7(1):15171. doi: 10.1038/s41598-017-15595-z.
A novel red-emitting phosphor NaY(SiO)O:Sm (NYS:Sm) was synthesized and the X-ray diffraction and high-resolution TEM testified that the NYS compound belongs to the apatite structure which crystallized in a hexagonal unit cell with space group P6/m. The novel phosphor boasts of such three advantageous properties as perfect compatible match with the commercial UV chips, 73.2% quantum efficiency and 90.9% thermal stability at 150 °C. Details are as follows. NYS:Sm phosphor showed obvious absorption in the UV regions centered at 407 nm, which can be perfectly compatible with the commercial UV chips. The property investigations showed that NYS:Sm phosphor emitted reddish emission with CIE coordination of (0.563, 0.417). The optimum quenching concentration of Sm in NYS phosphor was about 10%mol, and the corresponding concentration quenching mechanism was verified to be the electric dipole-dipole interaction. Upon excitation at 407 nm, the composition-optimized NYS:0.10Sm exhibited a high quantum efficiency of 73.2%, and its luminescence intensity at 150 °C decreased simply to 90.9% of the initial value at room temperature. All of the results indicated that NYS:Sm is a promising candidate as a reddish-emitting UV convertible phosphor for application in white light emitting diodes (w-LEDs).
合成了一种新型红色发光荧光粉NaY(SiO)O:Sm（NYS:Sm），X射线衍射和高分辨率透射电镜证明NYS化合物属于磷灰石结构，其在空间群为P6/m的六方晶胞中结晶。这种新型荧光粉具有与商用紫外芯片完美兼容匹配、73.2%的量子效率以及在150℃时90.9%的热稳定性这三个优势特性。具体如下。NYS:Sm荧光粉在以407nm为中心的紫外区域有明显吸收，可与商用紫外芯片完美兼容。性能研究表明，NYS:Sm荧光粉发出红色发射光，CIE坐标为(0.563, 0.417)。NYS荧光粉中Sm的最佳猝灭浓度约为10%mol，相应的浓度猝灭机制被证实为电偶极-偶极相互作用。在407nm激发下，成分优化后的NYS:0.10Sm表现出73.2%的高量子效率，其在150℃时的发光强度仅降至室温初始值的90.9%。所有结果表明，NYS:Sm作为一种用于白光发光二极管（w-LEDs）的红色发射紫外转换荧光粉是一个有前途的候选材料。
