Ce1-xGdxO2-δ固溶体中缺陷物种的拉曼光谱研究 |
Defect Sites in the Ce1-xGdxO2-δ Solid Solutions by Raman Spectroscopy |
|
摘要: 采用溶胶-凝胶法制备一系列Ce1-xGdxO2-δ固溶体。利用紫外(325 nm)和可见(514 nm)Raman光谱,X射线粉末衍射(XRD),透射电子显微镜(TEM)和紫外可见漫反射光谱(UV-Vis DRS),考察了Ce1-xGdxO2-δ固溶体的缺陷物种的分布以及Gd含量对缺陷浓度的影响。结果表明:Ce1-xGdxO2-δ固溶体中存在氧缺位(~560 cm-1)和GdO8型缺陷结构(~600 cm-1)。根据样品对Raman激发光的吸收,紫外Raman光谱反映样品的表层信息,可见Raman光谱反映样品的整体信息。Ce1-xGdxO2-δ固溶体表层氧缺位(να)和GdO8型缺陷物种的浓度(νβ)均高于固溶体体相,这归因于缺陷物种的表面富集。然而,相比于GdO8型缺陷物种,体相中氧缺位浓度增加较表层中的更显著。 |
关键词: Raman光谱 Ce1-xGdxO2-δ固溶体 缺陷物种 |
基金项目: |
Abstract: A series of Ce1-xGdxO2-δ solid solutions were prepared using a sol-gel method, Raman spectroscopy with 325 and 514 nm excitation wavelengths, X-ray diffraction (XRD), transmission electron microscopy images (TEM) and UV-Vis diffuse reflectance spectra (UV-Vis DRS) were used to analyze the distributions of defect sites in Ce1-xGdxO2-δ solid solutions and the effect of Gd content on their concentration. There were two defect sites of oxygen vacancies and GdO8-type complex corresponding to the Raman peaks at 560 cm-1 and 600 cm-1, respectively. The UV Raman spectroscopy could provide the surface information, while the Visible Raman spectroscopy could get the whole information of the sample. The concentration of oxygen vacancies and GdO8-type complex were higher on the surface than in the bulk due to the surface enrichment. However, comparing with the concentration of GdO8-type complex, the increase in the concentration of oxygen vacancies in the bulk was more obvious than that of in the surface. |
Keywords: Raman spectroscopy Ce1-xGdxO2-δ solid solutions defect sites |
|
摘要点击次数: 1803 |
全文下载次数: 2007 |
李 岚,胡庚申,陈 芳,罗孟飞.Ce1-xGdxO2-δ固溶体中缺陷物种的拉曼光谱研究[J].无机化学学报,2012,28(1):20-24. |
查看全文 查看/发表评论 下载PDF阅读器 |
Support information: |
|
|
|