Direct Observations of β″″-Structures in a K2O-Fe2O3-CdO System by High-Resolution Electron Microscopy

✍ Scribed by H. Takamura; E. Aoyagi; R. Aoki; T. Kagotani; M. Okada; S. Sugimoto; M. Homma

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 601 KB
• Volume: 113
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1994.1339

✦ Synopsis

The direct confirmation of the existence of Cd-stabilized (\boldsymbol{\beta}^{\prime \prime \prime}) ferrite prepared as a stable phase in a (\mathrm{K}{2} \mathrm{O}-\mathrm{Fe}{2} \mathrm{O}{3}-\mathrm{CdO}) system was done by high-resolution electron microscopy. It was confirmed that the Cd-stabilized (\boldsymbol{\beta}^{\prime \prime \prime})-ferrite had a rhombohedral symmetry with lattice constants (a=0.600) and (c=5.026 \mathrm{~nm}). The structure is composed of an alternate stacking of ion-conductive layers and spinel-like blocks which have six cubic close-packed oxygen layers expressed as (\cdots \mathrm{A}{1}(\mathrm{BCABCA}) \mathrm{B}{1}(\mathrm{CABCAB}) \mathrm{C}{1}(\mathrm{ABCABC}) \mathrm{A}_{1} \cdots). In addition, twins which had reversed stacking sequences were observed in the spinel-like blocks. 1994 Academic Press, Inc.