Oxygen-vacancy ordering in lanthanide-doped ceria: Dopant-type dependence and structure model
Oxygen-vacancy ordering in lanthanide-doped ceria: Dopant-type dependence and structure model
复制标题
DOI：
10.1103/physrevb.77.024108
复制
发表时间：
2008-01-01
影响因子：
3.7
通讯作者：
Drennan, John
中科院分区：
文献类型：
--
作者：
Ou, Ding Rong;Mori, Toshiyuki;Drennan, John
在15和25 at. %镧系元素（Ln）掺杂的氧化铈样品（Ln=Sm，Gd，Dy和Yb）的氧空位的局域有序性得到证实，氧空位随掺杂水平的增加而发展，其顺序为（Gd，Sm）>Dy>Yb。此外，随着掺杂浓度从15增加到25 at. %观察到。基于SAED谱的分析，建立了一个氧空位有序化的结构模型，该模型中氧空位的排列与C型Ln（2）O（3）氧化物中的氧空位的排列相似，空位的1/2< 110 >对是优先的。然后，讨论了影响有序形成的因素。
Studies of electron energy loss spectroscopy and selected area electron diffraction (SAED) were systematically performed on 15 and 25 at. % lanthanide (Ln)-doped ceria samples (Ln=Sm, Gd, Dy, and Yb), through which the local ordering of oxygen vacancies that develops with increase in doping level was confirmed in the sequence of (Gd,Sm)>Dy>Yb. Furthermore, a monotone correlation between the development of the ordering and the degradation of ionic conductivity with increasing the doping concentration from 15 to 25 at. % was observed. Based on the analysis of SAED patterns, a structural model for the ordering of oxygen vacancies has been constructed, in which the arrangement of oxygen vacancies is similar to that in C-type Ln(2)O(3) oxides and the 1/2 < 110 > pairs of the vacancies are preferred. Then, the factors that can influence the formation of the ordering are discussed.