【作者】 郭崇峰； 陈涛； 栾林； 张伟； 黄德修；

【Author】 GUO Chong-feng CHEN Tao LUAN Lin ZHANG Wei HUANG De-xiu (Wuhan National Laboratory for Optoelectronics,Huazhong University of Science and Technology,Wuhan 430074,China)

【机构】 华中科技大学武汉光电国家实验室；

【摘要】 采用溶胶-凝胶法合成了发光二极管（LED） 用 R_2-xEu_x（MoO₄）₃（R=Gd,Y,La；0≤x≤2）系列高亮度红色荧光粉,并对其结构与发光性能进行了详细研究．采用粉末 X 射线衍射（XRD）测量了不同温度下合成的样品结构变化情况,发现当 R=Y 和 Gd 时,它们具有单斜和正交两种结构；当 R=La 时,荧光粉只有一种单斜结构．同时用荧光光谱对它们的发光性能进行了研究,发现在相同条件下（相同温度,相同时间,相同浓度）得到的样品的发光强度顺序为 La_0．8EU_1．2（MoO₄）₃ ＞Gd_0．8Eu_1．2（MoO₄）₃＞Y_0．8Eu_1．2（MoO₄）₃,且它们在395 和465nm 均有较强的有效激发,这两种波长正好与商用的 GaN 基 LED 芯片相匹配．同时研究了煅烧温度及掺杂浓度对其发光性能的影响。更多还原

【Abstract】 Series of red emitting phosphor R_2-xEu_x（MoO₄）₃（R=Gd,Y,La:0≤x≤2）for white light emitting diode were prepared by sol-gel method.The effects of concentration of activator and heating temperature on crystal structure and luminescent properties were investigated by using XRD and fluorescent spectra.The XRD patterns showed that phosphor Gd_0．8EU_1．2（MoO₄）₃ and Yo_0．8Eu_1．2（MoO₄）₃ have monoclinic and orthorhombic two crystal structure,and the phosphor La_0．8Eu_1．2（MoO₄）₃ has only one monoclinic structure.Their excitation spectra show effective absorption wavelengths at near ultraviolet light（395nm）and blue light（465nm）corresponding to the f-f transition of Eu³⁺.These wavelengths coincide with the emitting light of commercial GaN-based LED,thus these phosphor may the better candidate for red emitting phosphor for white LED.The emission spectra exhibit most intense red light at 616nm,which is attributed to the ⁵D₀→⁷F₂ transition.Among these series of phosphors,the intensity of phosphor La_0．8Eu_1．2（MoO₄）₃ is the strongest,then is Gd_0．8Eu_1．2（MoO₄）₃ and Y_0．8Eu_1．2（MoO₄）₃ as the heating temperature at 900℃.更多还原