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以强碱性阴离子交换树脂为沉淀剂,采用离子交换法制备了ZrO_2:Eu~(3+)纳米晶.通过XRD,TEM,HRTEM和EDS等对晶体的结构,形貌及化学成分进行了表征,利用3D荧光光谱、激发光谱和发射光谱研究了Eu~(3+)在ZrO_2纳米晶中的发光性质.结果表明,焙烧温度在800℃以下所得的ZrO_2:Eu~(3+)纳米晶主要为四方结构,晶粒尺寸约为5-20 nm,随着焙烧温度的升高,样品的晶结构发生了细微变化,从900℃开始出现了少量单斜晶.由ZrO_2:Eu~(3+)的3D荧光光谱确定了其最佳监测波长和发射波长,在394 nm波长光的激发下观察到纳米ZrO_2中Eu~(3+)的590 nm(~5D0→~7F1)和606 nm(~5D0→~7F2)特征发射谱,随着相结构细微的变化,发射光谱的形状及强度均发生变化,说明ZrO_2:Eu~(3+)纳米晶的发光性质对其结构非常敏感.

Eu~(3+) doped luminescent nano-materials have become a research focus due to their outstanding physical and chemical properties in light-emitting, magnetism, thermology, catalysis and chemical activity etc.. Furthermore, the relationship between crystal structure and energy levels tran-sition of these nano-materials can be easily obtained by measuring the spectra of doped Eu3+>. Among luminescence nano-materials, ZrO_2 nano-crystal as a potential one has been attracted great attention in its higher refractive, good optical transparency and relatively low phonon energy. By now certain materials doped RE ion in the matrix ZrO_2 for ZrO_2; Er~(3+)-Y~(3+), ZrO_2: Pr~(3+) and ZrO_2: (Pr~(3+), Sm~(3+))etc., and mesoporous ZrO_2 nano-crystals doped Eu~(3+) by hydrothermal way have been reported. In present study, the ZrO_2: Eu~(3+) nano-crystal was prepared with high purity and uniform composition by ion exchange method using strong OH~- as a precipitant. Its composition, morphology and structure were characterized by XRD, TEM, HRTEM and EDS. The experimental results show that it has a tetragonal crystal structure and its average grain size is 5-20 nm after calcined at 800 ℃. It is found that the microstructure of ZrO_2 : Eu~(3+) changes slightly with the increase of calcining temperature till a small amount of monoclinic phase forms after calcined at higher than 900 ℃. The luminescentproperties of Eu~(3+) in the ZrO_2 nano-crystal were measured by 3D emission and excitation spectra. The characteristic emission bands of 590 nm (~5>D_0→~7F_1>) and 606 nm (~5D_0→~7F_2) of Eu~(3+) were observed at an excitation spectrum of λ_(ex)=394 nm. The luminescent properties of ZrO_2 : Eu~(3+) are very sensitive to its microstructure change since slight changes in the ZrO_2 : Eu~(3+) microstructure cause the changes in the shape and intensity of its emission spectra.