三角星状CeO_2微结构的合成与表征

Synthesis and Microstructures Characterization of Trigonometry-star-like CeO_2

以CeCl_3·7H_2O作为铈源、碳酸氢铵作为沉淀剂、乙二胺作为络合剂,采用水热法制备了三角星状二氧化铈微结构。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱仪(XPS)、拉曼光谱(Raman)、荧光分光光度计(PL)、紫外可见近红外分光光度计(UV-Vis)和综合物性测量系统(PPMS)等对此CeO_2样品的晶相、形貌、表面化学组分、缺陷、光学和磁学性质做了相关研究,分析并提出了三角星状二氧化铈微结构生长机理。结果表明,制备的Ce O_2具有室温铁磁性,其室温铁磁性与样品中Ce^(3+)和氧空位有关。样品对波长小于400 nm的紫外光有很强的吸收,但对波长大于400 nm的可见光有很好的透过性,这表明样品能很好的用做紫外吸收剂。

Trigonometry-star-like CeO_2 microstructures were successfully synthesized by hydrothermal method using CeCl_3·7H_2O as cerium source,NH_4HCO_3 as precipitant and ethylenediamine as the complexing agent. The crystal phases,morphology,surface chemical component,defects,optical and magnetic properties of the as-synthesized CeO_2 were studied by X-ray diffraction( XRD),scanning electron microscope( SEM), X-ray photoelectron spectroscopy( XPS), Raman spectrometer( Raman),fluorescence spectrophotometer( PL),Ultraviolet-visible-near-infrared spectrophotometer( UV-Vis) and comprehensive physical measurement system( PPMS). Growth mechanism of trigonometry-star-like CeO_2 microstructures was put forward. The results show that the as-synthesized trigonometry-star-like CeO_2 microstructures has room temperature ferromagnetism,which is likely associated with Ce^(3+)and oxygen vacancies. The as-synthesized sample has a strong absorption to ultraviolet light,however,but it has good permeability for visible light. This indicates that the sample can be well used as ultraviolet absorber.