Jia Yan, Jiang Hua, Valkeapää Markus, Yamauchi Hisao, Karppinen Maarit, Kauppinen Esko I
NanoMaterials Group, Department of Applied Physics and Center for New Materials, Helsinki University of Technology, P.O. Box 5100, FI-02015 TKK, Finland.
J Am Chem Soc. 2009 Apr 8;131(13):4880-3. doi: 10.1021/ja809745k.
Extraordinary oxygen ordering and mobility have been found in an oxygen-nonstoichiometric mixed-valence cobalt oxide, YBaCo(4)O(8.5). The excess oxygen atoms appear to be incorporated in an orderly way into the YBaCo(4)O(7) parent lattice with different configurations as the oxygen content varies. Intense electron-beam irradiation was used to observe recurrent oxygen migration in the lattice, causing reversible structural modulation transitions. The oxygen migration can be attributed mainly to the electron-beam heating effect. This study highlights the high degree of freedom of surplus oxygen within the investigated structure and advances our understanding of the oxygen diffusion process in related transition-metal oxide systems.
在一种氧非化学计量的混合价钴氧化物YBaCo(4)O(8.5)中发现了异常的氧有序排列和迁移率。随着氧含量的变化，过量的氧原子似乎以有序的方式以不同的构型并入YBaCo(4)O(7)母体晶格中。使用强电子束辐照来观察晶格中反复出现的氧迁移，从而导致可逆的结构调制转变。氧迁移主要可归因于电子束加热效应。这项研究突出了所研究结构中过剩氧的高度自由度，并增进了我们对相关过渡金属氧化物系统中氧扩散过程的理解。
