Sr^(2+)共掺杂LaPO_(4):Tb^(3+)发光材料的水热合成与性能

Sr^(2+)Co-Doped LaPO_(4):Tb^(3+)Phosphors:Hydrothermal Synthesis and Photoluminescence Properties

采用水热法制备Sr^(2+)共掺杂LaPO_(4):5%Tb^(3+)发光材料,通过X射线粉末衍射(XRD)、傅里叶变换红外光谱(FT-IR)、荧光光谱等对所制样品的物相结构和光学性能分析。探讨了反应体系的pH值、反应温度和Sr^(2+)离子的摩尔掺杂量等对样品物相结构及发光性能的影响。结果表明:采用水热法所制备的样品均为纯相的单斜晶系独居石结构Sr^(2+)共掺杂LaPO_(4):5%Tb^(3+)晶体,所制备样品在紫外光激发下发射出Tb^(3+)特征绿光。在反应体系pH值为2、水热反应温度为140℃和Sr^(2+)的掺杂量为1.5%(物质的量分数)的条件下制备的共掺杂LaPO_(4):5%Tb^(3+)样品发光性能最好,处于544 nm处发射峰的相对强度为单掺杂LaPO_(4):5%Tb^(3+)样品的2.8倍。

Sr^(2+)co-doped LaPO_(4):5%Tb^(3+)luminescent crystals were successfully prepared by a hydrothermal technique.The phase structures and optical properties of the as-synthesized samples were analyzed by X-ray powder diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR)and fluorescence spectroscopy.The influence of synthesis conditions such as the doping concentration of Sr^(2+),the pH values,and the reaction temperatures on the phase structures and optical properties of the as-prepared samples were also investigated.The results show that the pure phase of Sr^(2+)co-doped LaPO_(4):5%Tb^(3+)crystals with monoclinic monazite structure can be obtained in this way.The as-prepared samples emit the characteristic green light of Tb^(3+)ions under the excitation of UV light.The results reveal that the optimum synthesis conditions are that the pH of hydrothermal solution is 2,hydrothermal temperature is 140℃and the Sr^(2+)doping concentration is 1.5%.The sample obtained under the optimum conditions display 2.8 times of the relative intensities of the emission peak at 544 nm than that of the LaPO_(4):5%Tb^(3+)sample.