摘要
采用还原气氛下的高温固相法制备了Sr3SiO5:Eu2+橙色荧光粉,利用X射线衍射、扫描电子显微镜和荧光分光光度计考察了Ba2+与Sr2+替换和助熔剂对Sr3SiO5:Eu2+晶体结构和发光性能的影响。结果表明:Ba2+取代Sr2+会使配位多面体膨胀,导致附近Eu2+占据的配位多面体压缩,晶体场强度增大。随着Ba2+取代量的增加,Eu2+逐渐占据Ba2+取代后的多面体中心,晶体场强度减弱,发射光谱峰值整体先由575 nm红移至592 nm后又蓝移回583 nm。Sr2+与Ba2+的量比n(Sr):n(Ba)=4时,发射光谱红移效果最佳。助熔剂H3BO3的掺入会使Sr3SiO5:Eu2+的发光强度急剧下降。而NH4F和NH4Cl掺入都能使Sr3SiO5:Eu2+的发射光谱强度增大,NH4F和NH4Cl单掺质量分数分别为2%和0.3%时增强效果最好,且NH4Cl的增强效果比NH4F要好很多。
Sr3SIO5： Eu2＋ phosphors were synthesized by high temperature solid state reaction method under a reductive atmosphere. The effects of Baz ＋ substitution for Sr2＋ and fluxes on the crystal structure and the luminescent properties of Sr3SiO5 ： Eu2 ＋ phosphors were investigated by X-ray pow- der diffraction （XRD）, scanning electron microscopy （SEM）, and fluorescence spectrophotometer. The substitution of the host lattice cation Sr2＋ by Ba2 ＋ can make the polyhedron enlarged and then cause the shrinking of the neighboring Sr2＋ or Eu2＋ sites, which may explain an increased crystal field. Along with the increase of the Ba2 ＋concentration, Eu2 ＋ occupies the Ba2＋ site by degrees and the crystal field decreases. Thus, the emission wavelengths of the sample display red-shift from 575 nm to 592 nm at first and then blue-shift back to 583 nm. The maximum emission wavelength ap- pears when n（St） ： n（Ba） = 4. The experimental results also indicate that the influence of different flux on the luminescent intensity of the Sr3SiO5： Eu2＋ phosphors varied： H3BO3 decreased sharply, NHaF improved a little and NH4Cl improved greatly. The optimum mass fraction was 2% for NH4F and 0.3% for NH4Cl, respectively.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2013年第4期438-443,共6页
Chinese Journal of Luminescence
基金
国家自然科学基金(40643018)
大学生创新实验计划(101049109)资助项目
