He Long-Fei, Fan Guang-Han, Lei Mu-Yun, Lou Zai-Liang, Chen Zhi-Wu, Xiao Yao, Zheng Shu-Wen, Zhang Tao
Institute of Opto-electronic Materials and Technology, South China Normal University, Guangzhou 510631, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2013 May;33(5):1175-9.
High-purity ultrafine MgAl2O4 powder was synthesized by metal-alkoxide method and calcining for 2-4 h. And then MgAl2O4/Ce:YAG transparent 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 fluorescence 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 ceramic was 59.74 ns. All results show that MgAl2O4/Ce:YAG transparent ceramic may be a promising fluorescent material for white LED applications.
采用金属醇盐法合成了高纯度超细MgAl2O4粉末，并煅烧2 - 4小时。然后，以YAG:Ce粉末和MgAl2O4粉末为原料，通过热压烧结和热等静压烧结技术制备了MgAl2O4/Ce:YAG透明陶瓷。分别采用XRD、SEM、EDS和荧光光谱仪对透明陶瓷进行了表征。结果表明，透明陶瓷的晶相由MgAl2O4和YAG组成，YAG相在MgAl2O4基体中分散良好。激发光谱在345 nm处有一个弱带，在475 nm处有一个强带。约533 nm处的宽发射峰归因于Ce3+离子的5d→4f跃迁。MgAl2O4/Ce:YAG透明陶瓷荧光测试的衰减曲线表明，Ce:YAG玻璃陶瓷的寿命为59.74 ns。所有结果表明，MgAl2O4/Ce:YAG透明陶瓷可能是一种有前途的用于白光发光二极管应用的荧光材料。
