近紫外LED用黄色荧光粉Sr3 SiO5.Ce3+,Li+的发光特性

摘要

Sr3 SiO5:Ce3+, Li+ phosphors were synthesized by the high temperature solid state reac-tion method. The crystal structure and luminescent properties of the samples were analyzed by X-ray diffraction and fluorescence spectrophotometer. Sr3-2x SiO5: xCe3+, xLi+ samples with tetragonal phase structure can be synthesized at 1 420 ℃. The excitation spectral distribution is in the near-ultraviolet range of 270 ~ 500 nm with two bands, and the double peak positions are located at 328 nm and 410 nm, respectively. The emission spectrum under 410 nm near-ultrviolet excitation shows a broad band centered at 528 nm. The optimum doping content of Ce3+ is x(Ce3+) =0. 8%. With the increase of doping concentration, the luminescence intensity firstly increases and then decreases because of the concentration quenching effect. The concentration quenching is attribute to the dipole-dipole interaction of Ce3+, according to Dexter theory.%采用高温固相法快速降温合成Sr3-2x SiO5.xCe3+,xLi+荧光粉。用X射线衍射仪和荧光分光光度计测试荧光粉的样品结构和发光性能。在1420益下煅烧得到四方相结构的Sr3 SiO5.Ce3+,Li+。样品的激发光谱分布于270~500 nm的波长范围,有两个激发带,峰位分别位于328 nm和410 nm,表明样品可以被近紫外光有效激发。样品的发射光谱分布于420~650 nm,发射峰位于528 nm处。在410 nm左右的近紫外光激发下,宽带发射的峰位于528 nm。 Ce3+的最佳掺杂量x(Ce3+)为0.8%,并且发光强度随掺杂浓度的增加先升高后降低,出现浓度猝灭。根据Dexter能量共振理论,该浓度猝灭的原因是Ce3+的电偶极-电偶极相互作用。