知识与财富的链接
采用 XRF、XRD、Raman、XPS、H2-TPR 以及与氩离子刻蚀相结合的XPS等表征技术对柠檬酸溶胶-凝胶法制备的Ce1-xZrxO2 (0≤x≤1)样品的结构及其氧移动性进行了研究. 结果表明, Ce1-xZrxO2 样品的晶型结构对其中氧的移动性有明显影响. 当x≤0.15 时, Ce1-xZrxO2 以立方CeO2相 Ce-Zr-O 固溶体存在, 随着Zr含量的逐渐增加, CeO2晶胞体积减小、氧空位浓度增加, 氧移动性逐渐增强; 当x＞0.15时, 形成四方ZrO2相和立方CeO2相Ce-Zr-O固溶体的混合物, 随着Zr含量的逐渐增加, 四方ZrO2相的含量增加、氧空位浓度减小, 氧移动性逐渐减弱. 因此, Ce0.852Zr0.152O2样品具有最高的氧移动性.
The structure and oxygen mobility of Ce1-xZrxO2 (0 ≤x≤ 1) samples prepared by citric acid sol-gel method were characterized by XRF, XRD, Raman, XPS, Ar+ etching-XPS and H2-TPR. The data showed that the crystalline structure of Ce1-xZrxO2 can significantly affect the oxygen mobility. When x≤0.15, the samples were found to exist as cubic Ce-Zr-O solid solutions. An increase in x resulted in a shrinking of the crystal unit volume, an increasing in the number of oxygen vacancies, and an increasing in the oxygen mobility as well. When x＞0.15, Ce1-xZrxO2 existed in a mixed phases of tetragonal and cubic Ce-Zr-O solid solutions; the percentage of tetragonal phase increased, oxygen vacancies decreased and oxygen mobility reduced with increasing x in these samples. Therefore, this present work shows that oxygen mobility in the Ce0.85Zr0.152O2 sample is the highest.
