Novel solid-state approaches for the synthesis of calcium stannate for BaTiO3-CaSnO3 capacitor ceramics

• Published in: Ceramics international 2024-12
• Main Authors: Ivakin, Yurii D., Kornyushin, Maksim V., Mushtakov, Anton G., Kholodkova, Anastasia A., Khrustalev, Arseniy N., Arbanas, Levko A., Bazarova, Viktoria E., Akin'shin, Ivan D., Shumyantsev, Alexey V., Kharlanov, Andrey N., Chistyakov, Vladimir D., Muravieva, Galina P., Sokolov, Dmitry A., Smirnov, Andrey V.
• Format: Article
• Language: English
• Subjects: Barium titanate; Calcium stannate; Capacitor ceramics; Dielectric constant; Solid state synthesis; Supercritical water
• ISSN: 0272-8842
• DOI: 10.1016/j.ceramint.2024.12.164

The paper was aimed to study a novel synthesis approach for CaSnO3 fine powder utilizing vapor or supercritical water as a reaction medium at temperatures of 270–400 °C. The synthesized powders were investigated by XRD, SEM, DRIFTS, thermal and dilatometric analysis and compared to CaSnO3 powder prepared by a conventional solid-state synthesis at 1400 °C. In a water medium, the initial oxides transformed through intermediate CaSn(OH)6 and another phase into CaSnO3 powder with an average crystal size of 5.14 ± 0.06 μm, containing traces of SnO2 and 0.7 wt % of structural water. Formation of CaSnO3 at this low temperature was explained by the appearance of a solid-phase mobility of the oxide structures promoted by the water medium. Synthesized in supercritical water, CaSnO3 powders was applied for preparation of BaTiO3-0.15CaSnO3 ceramics, which performed superior dielectric properties at a low frequency range (dielectric constant up to 14131 and loss tangent of 0.02).