【摘要】 以La2O3、Eu2O3和氨水等为原料,采用水热法合成了(La0.95Eu0.05)(OH)3一维纳米线前驱体,并经适当煅烧制备了(La0.95Eu0.05)2O3红色荧光粉。系统考察了反应体系pH值对产物的影响。通过X射线衍射、红外光谱、场发射扫描电镜、高分辨透射电子显微镜和差热分析、荧光光谱分析等手段对产物进行了系统表征。结果表明所得氢氧化物纳米线具有多晶构造、表面平滑且结晶良好,其长度和直径分别约为800~1000 nm和40~50 nm。该氢氧化物前驱体于800℃以上煅烧可分解为结晶良好的氧化物,且所得氧化物荧光粉在288 nm电荷转移带激发下于约630 nm处呈现鲜艳的红色荧光发射,归属于Eu3+的5D0→7F2跃迁。更多还原

【Abstract】 ( La0. 95Eu0. 05)( OH)3 nanowire precursors( Ln = La,Eu) were prepared via hydrothermal reac-tion using La2O3,Eu2O3,and ammonium hydroxide as raw materials,which were then converted into oxide phosphors via proper annealing. The effects of solution pH on precursor properties were studied. The systematic characterizations of the products were achieved by the combined techniques of X-ray diffraction,Fourier transform infrared spectroscopy,scanning electron microscopy, transmission electron microscopy, thermo gravimetric analysis / differential scanning calorimetry, and photoluminescence excitation / emission spectroscopies. The results indicated that the hydroxide nanowires are well crystallized,polycrystalline with smooth surface,and the lengths and diameters are ~ 800 ~ 1000 nm and 40 ~ 50 nm,respectively. Well crystallized La2O3 : Eu3 +red phosphors were obtained by calcining the hydroxide precursors at temperatures higher than > 800 ℃. Upon UV excitation into the charge transfer band at 288 nm,the oxide phosphors showed the strongest red emission at 630 nm,arising from the5D 0 →7F2 forced electric dipole transition of Eu3+.更多还原