A Mössbauer study of oxygen vacancy and cation distribution in 6H-BaTi1−xFexO3−x/2
A Mössbauer study of oxygen vacancy and cation distribution in 6H-BaTi1−xFexO3−x/2
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DOI：
10.1016/j.jssc.2003.08.008
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发表时间：
2004
影响因子：
3.3
通讯作者：
E. Mashkina;C. McCammon;F. Seifert
中科院分区：
文献类型：
--
作者：
E. Mashkina;C. McCammon;F. Seifert
在还原氧逸度的条件下，在温度1200 ~ 1300℃，x=0.1 ~ 0.6的BaTi{sub - 1-x}Fe{sub -x} O{sub - 3-x/2}体系中合成了样品。液滴淬火后，用电子探针、x射线衍射和穆斯堡尔能谱对样品进行了表征。所有样品均为六边形，具有6H-BaTiO{sub 3}型结构。Moessbauer光谱显示所有的铁都以Fe{sup 3+}的形式存在，出现在八面体和五面体的位置。面积比分析表明氧空位在O1位点上随机分布，而Fe和Ti离子在M1和M2位点上的随机分布与数据一致。没有发现氧空位排序的证据。结果与电导率结果一致，表明随着氧空位浓度的增加，离子电导率普遍增加。
We have synthesized samples in the system BaTi{sub 1-x}Fe{sub x}O{sub 3-x/2} with x=0.1-0.6 at temperatures of 1200-1300 deg. C under reducing conditions of oxygen fugacity. After drop quenching, samples were characterized using the electron microprobe, X-ray diffraction and Moessbauer spectroscopy. All samples were hexagonal with a 6H-BaTiO{sub 3} type structure. Moessbauer spectroscopy showed all iron to be present as Fe{sup 3+}, occurring in octahedral and pentahedral sites. Analysis of area ratios indicates that oxygen vacancies are distributed randomly over O1 sites, and that a random distribution of Fe and Ti cations over M1 and M2 sites is consistent with the data. No evidence for ordering of oxygen vacancies was found. Results are consistent with conductivity results, which show generally increasing ionic conductivity with increasing oxygen vacancy concentration.