SO_4^(2-)对BaSO_4-2SiO_2∶Eu^(3+)发光材料的影响

Effect of SO_4^(2-) on luminescent materials BaSO_4-2SiO_2∶Eu^(3+)

采用溶胶-凝胶法与沉淀法制备了以BaSO4-2SiO2为复合基质的掺杂稀土Eu3+的发光材料,表征了材料的结构,研究了材料的发光性质,重点研究了SO2-4的量对材料发光强度的影响。IR光谱显示:600℃退火处理后材料主要存在Si-O-Si键、Ba-O键和SO2-4基团。XRD测试证明:BaSO4以晶态形式存在,属单斜晶系,SiO2以非晶态形式存在。激发光谱和发射光谱图显示,当掺入的SO2-4量为n(SO2-4)=n(Ba2+)+3/2n(Eu3+)时,SO2-4能有效提高发光材料的发光强度,紫外-可见吸收光谱测试显示SO2-4有很强的吸收紫外光的能力,且其激发态的能级和激活剂激发态能级处于有效传递范围,故能将吸收的能量有效地传递于发光离子,有助于材料发光强度的提高,最后结合能级图对SO2-4的能量传递体进行了说明和探讨。

Eu^3＋doped BaSO4^2-SiO2 luminescent materials were synthesized by sol-gel method and precipitation method.The crystal structure and luminescent properties of the samples were characterized.The effects of the amount of SO4^2-on the luminous intensity were focused on.IR results showed that the samples existed mainly in the form of the bond of Si-O-Si,Ba-O and SO42-groups after annealing at 600℃.XRD indicated that BaSO4 existed in crystalline form,belonging to monoclinic system,and SiO2 existed in amorphous form.The excitation and emission spectra showed that SO4^2- can effectively improve the luminous intensity of the materials when the amount of SO4^2- just reached n（SO4^2-）=n（Ba^2＋）＋3/2n（Eu^3＋）.The ultraviolet-visible absorption spectrum demonstrated that SO4^2-provided with strong ability to absorb ultraviolet light,and the energy level of the excited state of SO4^2- and activator was in the effective transmission range,therefore,it can make energy transfer effectively to glowing ion,which was conducive to improving the luminous intensity.Finally,the further explanation and discussion about the energy transfer of SO4^2- combined with the theory of energy level were conduced.