- 著者
- Wataru UNO Kotaro FUJII Eiki NIWA Shuki TORII Ping MIAO Takashi KAMIYAMA Masatomo YASHIMA
- 出版者
- 公益社団法人 日本セラミックス協会
- 雑誌
- Journal of the Ceramic Society of Japan (ISSN:18820743)
- 巻号頁・発行日
- vol.126, no.5, pp.341-345, 2018-05-01 (Released:2018-05-01)
- 参考文献数
- 46
- 被引用文献数
- 24
Crystal structure and neutron scattering length density distribution of a pyrochlore-type ytterbium titanate Yb2Ti2O7 have been investigated by in situ neutron powder diffraction measurements at 293 and 1173 K, Rietveld analysis and maximum-entropy method (MEM). In the MEM neutron scattering length density distributions of Yb2Ti2O7, the oxide ion O48f bonding to Ti cation was relatively localized at lower temperature of 293 K, while it was largely distributed at a higher temperature of 1173 K. At 1173 K, one oxide-ion diffusion path along the 〈110〉 unshared edge of TiO6 octahedron was clearly visualized and the other oxide-ion diffusion path along 〈100〉, strictly 〈2 −8x(O48f) + 3 8x(O48f) − 3〉, shared edge of TiO6 octahedron was also indicated. Here x(O48f) is the atomic coordinate x of O48f anion. The MEM neutron scattering length density distribution and difference bond valence sum map at 1173 K strongly suggested that the energy barrier for oxide-ion migration along 〈110〉 directions was lower than that along the 〈100〉 one. Oxide ions three-dimensionally diffuse through both the 〈110〉 and 〈100〉 paths across the unit cell.
- 著者
- Shungo TAKANO Kiyoto SHIN-MURA Eiki NIWA Takuya HASHIMOTO Kazuya SASAKI
- 出版者
- The Ceramic Society of Japan
- 雑誌
- Journal of the Ceramic Society of Japan (ISSN:18820743)
- 巻号頁・発行日
- vol.126, no.6, pp.482-487, 2018-06-01 (Released:2018-06-01)
- 参考文献数
- 32
- 被引用文献数
- 1 6
Sr2MgMoO6−δ (SMM) is one of promising anode materials for direct internal reforming solid oxide fuel cells as its excellent performance has been demonstrated. However, it is necessary to be chemically compatible with the electrolyte material to realize the original performance. In this study, we investigate chemical compatibility between SMM and typical electrolyte materials (8% mol Y2O3–92% mol ZrO2; YSZ, 10% mol Sc2O3–1% mol CeO2–89% mol ZrO2; ScSZ, La0.9Sr0.1Ga0.8Mg0.2O3−δ; LSGM) and anode interlayer materials (Gd0.1Ce0.9O2−δ; GDC, Ce0.8La0.2O2−δ; LDC) under conditions for preparing SMM electrode and operation. SMM formed a reaction layer with all of the typical electrolyte materials studied. LDC was the only material for the interlayer that maintains chemical compatibility with SMM, though it forms the reaction layer with YSZ and ScSZ. From these results, this study clarifies that LSGM and LDC should be used as electrolyte and interlayer, respectively, when SMM is used as the anode.