LED用荧光粉Ca_xMg_(9-x)(SiO_4)_4Cl_2∶Eu^(2+)发光性质的研究

Luminescence Properties of Phosphors Ca_xMg_(9-x)(SiO_4)_4Cl_2∶Eu^(2+) for LED

采用高温固相法合成氯硅酸镁钙荧光粉CaxMg9-x(SiO4)4Cl2∶0.08 Eu2+.首先借助X射线衍射对发光粉体晶格结构进行分析.分析结果表明:该荧光粉体具有面心立方晶系结构,钙镁配比的改变对晶体的结构没有产生较大影响.其次研究其荧光光谱和发光特性,研究结果表明:CaxMg9-x(SiO4)4Cl2∶0.08Eu2+荧光粉的激发光谱均为宽带激发,激发带位置范围为260~460nm,发射光谱发射峰的位置位于505 nm,归属于Eu2+产生的d-f跃迁发射.同时讨论不同钙镁离子配比对荧光粉发光性能的影响,当Ca/Mg离子配比为6~7.5时,荧光粉的发光强度有较大幅度的提高.

phosphors have been synthesized by high-temperature solid-state reaction. The structure of crystal lattice of the samples was examined on an X-ray diffractometer. The results show that the structure of the phosphors is face-centred cubic, and the changing ratios of calcium to magnesium have no obvious influence on crystal structure. The luminescence properties of the phosphors were studied, and show that the broadband excitation spectra ranges from 260 - 460 nm. The maximum emission wavelength is 505 nm attributed to d-f transition of Eu^2＋. The luminescence properties influenced on the different ratios of calcium to magnesium were also discussed The characteristic emission intensity of Eu^2＋ reaches higher when the content of Ca is 6 - 7.5, and compared to the phosphor CaxMg9-x（SiO4）4Cl2∶Eu^2＋, the luminescene intensity was improved significantly.