MgAl_2O_4/Ce∶YAG透明陶瓷的制备及光学性能

Preparation and Optical Properties of MgAl_2O_4/Ce∶YAG Transparent Ceramics

采用金属醇盐法制备MgAl2O4前躯体,通过高温煅烧2～4h得到纯相MgAl2O4粉体,再将其与YAG∶Ce荧光粉均匀混合,利用热压烧结并结合热等静压处理得到MgAl2O4/Ce∶YAG透明陶瓷。利用XRD,SEM,EDS和荧光光谱仪对样品进行物相和光学性能分析。实验表明样品由MgAl2O4和YAG两相组成,YAG晶粒均匀地分散在MgAl2O4基质中。样品在340和475nm有两个激发峰。发射光谱在533nm处有一宽峰,属于Ce3+的5d→4f特征跃迁发射,其荧光寿命为59.74ns。结果表明,MgAl2O4/Ce∶YAG透明陶瓷是一种可用于白光LED的新型荧光材料。

High-purity ultrafine MgAl2O4 powder was synthesized by metal-alkoxide method and calcining for 2-4 h. And then MgAl2O4 /Ce ： YAG tra nsparent ceramics were fabricated by hot-pressed sintering and hot isostatic pressed sintering technique with YAG ： Ce powder and MgAl2O4 powder. The transparent ceramics were characterized by XRD, SEM, EDS and fluores- cence spectrometer, respectively. The results show that the crystal phase of the transparent ceramic was composed of MgAl2O4 and YAG, and the YAG phase dispersed well in the matrix of MgAl2O4 . The excitation spectra had a weak band at 345 nm and a strong band at 475 nm. The broad emission peaks at about 533 nm were attributed to 5d→4f transition of Ce3＋ ions. Decay curves for the fluorescence of MgAl2O4/Ce ： YAG transparent ceramic test show that the lifetime of the Ce：YAG glass ceram- ic was 59.74 ns. All results show that MgAl2O4/Ce ： YAG tra nsparent ceramic may be a promising fluorescent material for white LED applications.