以一缩二乙二醇为溶剂,采用多醇法(polyol method)合成LaPO4:Eu^3+纳米发光材料,利用XRD、FE.SEM、TG-DTA、Uv-vis光谱、光致发光光谱(PL)及寿命等手段进行了表征。结果表明:所得到的材料结晶完好,具有LaPO4的独居石型结构;粒子的形貌为球形,其粒径约为25nm;在波长为258nm的紫外光激发下,其发射光谱由Eu^3+的5D0^-7FJ(J=1,2,3,4)特征发射组成,在592nm处的磁偶极跃迁(5D0^-7F1)最强,表现为Eu^3+的橙-红特征发射;LaP04:Eu^3+纳米粒子中Eu^3+的最佳掺杂浓度为5%(摩尔比);Eu^3+的光致发光衰减曲线符合单指数行为,其寿命(τ)为3.9ms。
Eu^3+ -doped LaPO4 nanoparticles were prepared by polyol method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy ( FE-SEM ), thermogravimetry-differential thermal analysis ( TG-DTA ), Uv-vis diffuse reflectance spectra (DRS), photoluminescence (PL) spectra and lifetime measurement. The results of XRD indicate that the as-prepared nanoparticles are crystallized well at 160 ℃ and assigned to the monoclinic monazite-structure of LaPO4 phase. The obtained LaPO4: Eu^3+ nanoparticles are spherical with narrow size distribution and the average size of 25 nm. Upon excitation into the Eu^3+ at 258 nm, the emission spectrum of LaPO4 : Eu^3+ nanoparticles is composed of ^5D0 -^7FJ(J = 1, 2, 3, 4) emission lines of Eu^3+, with the magnetic-dipole transition ^5D0 -^7F1 (592 nm) being the most prominent group. This is characterized by orange-red emission. The optimum doping concentration of Eu^3+ is 5 % (molar fraction) of the La^3+ concentration in the LaPO4:Eu^3+ nanoparticles. The luminescence decay curve of LaPO4 : Eu^3+ nanoparticles shows single-exponential behavior, and the lifetime (τ) of Eu^3+ is about 3.9 ms.