类球状和棒状Eu_2O_3和Sm_2O_3纳米粒子的合成与表征

Fabrication and Characterization of Sphere-like and Rod-like Eu_2O_3 and Sm_2O_3 Nanoparticles

采用表面活性剂和超声波辅助的沉淀法合成了类球状和棒状多晶Eu2O3和Sm2O3纳米粒子,并用透射电镜（TEM）、选区电子衍射（SAED）、X射线衍射（XRD）、N2吸附-脱附和紫外-可见漫反射（UV-Vis DRS）技术表征了其物理性质.结果表明,以十二烷基硫酸钠作表面活性剂所得产物为类球状体心立方晶相Eu2O3和单斜晶相Sm2O3纳米粒子,比表面积为44-49 m^2/g;而以聚乙烯吡咯烷酮作表面活性剂所得产物则是棒状正交晶相Eu2O3和体心立方晶相Sm2O3纳米粒子,比表面积为34-37 m2/g.除了在紫外光区（λ〈390 nm）有较强的吸收外,类球状和棒状Eu2O3和Sm2O3纳米粒子在可见光区（390 nm〈λ〈535 nm）也有不同程度的吸收.该吸光性能差异与所得稀土氧化物的表面形貌和晶体结构有关.

Sphere-like and rod-like Eu2O3 and Sm2O3 polycrystalline nanoparticles were fabricated by using a surfactant-and ultrasonic-assisted precipitation strategy.The physical properties of these nanomaterials were characterized by means of transmission electron microscopic（TEM）,selected area electron diffraction（SAED）,X-ray diffraction（XRD）,nitrogen adsorption-desorption,and ultravioletvisible diffuse reflection spectroscopic（UV-Vis DRS） techniques.It is shown that the sphere-like body-centered cubic Eu2O3 and monoclinic Sm2O3 nanoparticles obtained with sodium dodecylsulfate as surfactant and the rod-like orthorhombic Eu2O3 and body-centered cubic Sm2O3 nanoparticles fabricated with polyvinylpyrrolidone as surfactant possessed a BET surface area of 44～49 and 34～37m2/g,respectively.In addition to a stronger absorption of UV light（λ390nm）,the sphere-like and rod-like Eu2O3 and Sm2O3 samples exhibited different absorption of visible light（390nmλ535nm）.Such a difference in light absorption behavior might be a result due to various surface morphologies and crystal structures of the so-obtained rare earth oxides.