Gd1-xEuxAl3(BO3)4纳米晶的合成及其发光性能

以高温固相反应法合成了Gd_1-xEu_xAl₃(BO₃)₄:Eu³⁺纳米荧光粉。使用XRD分析确定了样品的物相,并根据谢乐公式计算出其微晶的纳米粒度。采用了“粉末悬浮法”以甘油为分散介质,在RF540荧光光度计上测试了纳米晶荧光粉的激发光谱和发射光谱。GdAl₃(BO₃)₄基质本身发光,GdAl₃(BO₃)₄:Eu纳米荧光粉表现了Eu³⁺的特征发射光谱,其中最强峰为⁵D₀→⁷F₂发射,表明晶体结构中没有对称中心格位。实验表明在GdAl₃(BO₃)₄:Eu纳米晶荧光粉中,存在Gd³⁺对Eu³⁺发光的基质敏化作用。

Synthesis and Luminescence of Nano-microcrystal of Gd1-xEuxAl(BO3)4

REAl₃(BO₃)₄ was well known as good laser materials,but its fluorescent nano-powders have not been well studied.A series of fluorescent nano-powders Gd_1-xEu_xAl₃(BO₃)₄ has been synthesized by solid reactions.Raw materials Al₂O₃,H₃BO₃,Gd₂O₃,Eu₂O₃ were well mixed and baked at 400℃/2h first,then 750℃/4 h,and 1150℃/8h the last.After being well grinded the fluorescent powders of Gd_1-xEu_xAl₃(BO₃)₄ has been synthesized.The samples were characterized by XRD,and the microcrystal diameter of the samples were calculated to be within 100 nanometer by XRD diagram.Their luminescent properties of the fluorescent powders were measured by the RF540 fluorescence spectrometer(Japan)with “suspending powder method” with glycerin as the dispersing medium.The samples of GdAl₃(BO₃)₄ gave the emission spectrum at 310 nm when excited by the light of 280 nm,and the spectrum of dispersing medium glycerin did not disturb the spectrum of GdAl₃(BO₃)₄.The samples of Gd_1-xEu_xAl₃(BO₃)₄ almost had the same emission spectrum of Eu³⁺ no matter they were excited by 390 nm or by 280 nm.The strongest emission of Eu³⁺ was ⁵D₀→⁷F₂ transition.So there was no symmetry position in the crystal structure of Gd_1-xEu_xAl₃(BO₃)₄ by the rule of fluorescent probe.The emission spectrum of ⁵D₀→⁷F₂ was higher excited by 280 nm than that excited by 390 nm.It was the evidence of the energy transfer between Gd³⁺-Eu³⁺.The experiment results show that fluorescent powders with nanometer microcrystals of Gd_1-xEu_xAl₃(BO₃)₄ can be synthesized by solid reactions.GdAl₃(BO₃)₄:Eu³⁺ gives 618 nm emission spectrum as the transition ⁵D₀→⁷F₂,and there was no symmetry position in the crystal structure of Gd_1-xEu_xAl₃(BO₃)₄.The experiment results show that there was energy transfer between Gd³⁺-Eu³⁺.Because of its fine properties of fluorescence and its stability of material,the fluorescent nano-powders of Gd_1-xEu_xAl₃(BO₃)₄ may possess great value for being further studied and used.