外文题目: Influence of Ce ion Concentration on Fluorescence Properties of Ce: TAG-Al2O3 Eutectic Mixed Crystals
作者: He, Chongjun; Sai, Qinglin; Xia, Changtai; Hu, Huiling
刊名: Cryst. Res. Technol.
年: 2017 卷: 52 期: 7 文章编号：1700056
英文关键词:
eutectic mixed crystal; Ce-doped; photoluminescence; white LED
TERBIUM ALUMINUM GARNET; LIGHT-EMITTING DIODE; TAG SINGLE-CRYSTALS; GROWTH; TB3AL5O12; PHOSPHORS
英文摘要:
Combining a blue LED chip with phosphor, white light can be obtained. In traditional white LEDs, the phosphor was dispersed in resin in a form of particles. Particle-resin composite has complex packaging and poor thermal stability. For high-power white LEDs, this combination cannot provide long-term stable work because of photo-degradation of the organic epoxy resin under high irradiation and high temperatures. Here we develop resin-free phosphor (Tb(1-n)Cen)(3)Al5O12-Al2O3 eutectic mixed crystals (Ce: TAG-Al2O3) to eliminate the photo-degradation issue of the organic material. They were grown by optical floating zone method. X-ray diffraction and scanning electron microscopy show that these materials have typical eutectic mixed crystal structure of sapphire and garnet phases, in which lamellar spacing is in an order of tens of microns. The doped Ce3+ ions do not influence basic structure of TAG crystal. Ce3+ ion replaces Tb3+ ion rather than Al3+ ion. Photoluminescence emission and excitation properties of the eutectic mixed crystals were investigated. They get to maximal value with 2.0% Ce-3+,Ce- and have wide excitation band at 470 nm. Luminous efficiency of eutectic mixed crystal- packaged LED is higher than that of particle- resin composite packaged LED. These results show that Ce: TAG-Al2O3 eutectic mixed crystals are promising phosphor for white LEDs.


文献类型: 期刊论文
正文语种: English
收录类别: SCI
DOI: 10.1002/crat.201700056


全文传递服务