- 著者
- SUZUKI Yoshikazu MORIMOTO Masafumi
- 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.118, no.1381, pp.819-822, 2010-09
- 被引用文献数
- 21
Porous ceramics based on refractory double oxides are promising for the next-generation diesel particulate filter (DPF) materials. Similarly to aluminum titanate (Al2TiO5), MgTi2O5 has a pseudobrookite-type crystal structure with low thermal expansion coefficients among oxides. Since MgTi2O5 has higher stability of pseudobrookite phase than Al2TiO5, it is expected that MgTi2O5-based materials are suitable for the next-generation DPF materials. In this study, porous MgTi2O5/MgTiO3 composites have been prepared by in situ processing (viz. reactive sintering) at 1000–1200°C. Porous MgTi2O5/MgTiO3 composites with very narrow pore-size distribution at the diameter of ∼1 µm were obtained by the pyrolytic reactive sintering at 1000–1100°C. Internal pore-structure was characterized by mercury intrusion–extrusion porosimetry.
1 0 0 0 OA Water vapor-assisted solid-state reaction for the synthesis of nanocrystalline BaZrO3 powder
- 著者
- KOZAWA Takahiro YANAGISAWA Kazumichi SUZUKI Yoshikazu
- 出版者
- Ceramic Society of Japan
- 雑誌
- Journal of the Ceramic Society of Japan (ISSN:18820743)
- 巻号頁・発行日
- vol.121, no.1411, pp.308-312, 2013-03
- 被引用文献数
- 13 4
Solid-state reaction between BaCO3 and ZrO2 is the simplest method to prepare BaZrO3, which is an important refractory structural material with a very high melting point and a low chemical reactivity. However, since the solid-state formation of the BaZrO3 phase requires high calcination temperature, this method typically produces larger particles unsuitable for the sintering process than the solution methods. In this study, we investigated the reaction behavior between very fine ZrO2 (70 nm) and coarse BaCO3 (1.5–5.7 µm) and described the water vapor-assisted solid-state synthesis of BaZrO3. Nanocrystalline BaZrO3 powder (~80 nm) was obtained by solid-state reaction at 1050°C in air. The BaZrO3 formation was accelerated by water vapor-assisted reaction. The apparent activation energy for the formation reaction was calculated to be 323 ± 21 kJ/mol and 263 ± 46 kJ/mol in air and humid air with H2O of 0.5 atm, respectively. In the 1 atm water vapor atmosphere, almost single-phase BaZrO3 was obtained by calcination at 750°C.