沉淀法制备形貌可控YVO_4:Eu^(3+),Bi^(3+)粉体及其发光性能

Morphology-controlled Precipitation Synthesis and Luminescent Properties of YVO_4:Eu^(3+),Bi^(3+) Powder

采用沉淀法合成了YVO4:Eu3+,Bi3+荧光粉,利用XRD,SEM和TEM对样品的结构和形貌进行表征,并用荧光光谱仪测试了样品的激发和发射光谱。X射线衍射图分析表明,所制得的荧光粉与YVO4的物相一致,样品属于体心四方相。其扫描电镜和透射电镜照片显示颗粒为纺锤形,大小比较均匀,长径为250nm左右,短径为100nm左右。在275nm近紫外光激发下,该荧光粉的发光峰分别归属于Eu3+的5 D0→7 F1(596nm),5 D0→7F2(617nm,621nm),5 D0→7F3(654nm),5 D0→7F4(702nm)辐射跃迁。最强发射位于617nm左右,属于红光。研究了Eu3+浓度对样品发光强度的影响。随着Eu3+浓度的增加,发射峰强度增大,当Eu3+摩尔分数为12%时,峰值强度最大。Bi3+对Eu3+的发光有一定的敏化作用,当Bi3+摩尔分数达到5%时,敏化作用最强。

YVO4：Eu3＋,Bi3＋ phosphors were synthesized by a precipitation method.The structure and morphology of the products were characterized by XRD,FE-SEM,and TEM.The exitation and emission spectra of the products were investigated by fluorescence spectrometer.The X-ray diffraction（XRD） patterns showed that the powder was a body-centered tetragonal YVO4 phase.The SEM and TEM images showed that the YVO4：Eu3＋,Bi3＋ particles were spindle in shape with a mean diameter of 250 nm and minimum as 100 nm.The emission spectra of YVO4：Eu3＋,Bi3＋ phosphors have several emission peaks corresponding to the 5D0→7F1（596 nm）,5D0→7F2（617 nm,621 nm）,5D0→7F3（654 nm） and 5D0→7F4（702 nm） transitions of Eu3＋.The effect of Eu3＋ concentration on the emission intensity of YVO4：Eu3＋,Bi3＋ was investigated,and the results showed that the emission intensity increased with the increment of Eu3＋ concentration,reaching a maximum value at 12% of Eu3＋ concentration.It was also found that Bi3＋ could increase the emission intensity of Eu3＋,reaching a maximum value at 5% of Bi3＋.