The Influence of the Additive BaGeO3 on BaSnO3 Ceramics

23 PAGES (4214 WORDS) Chemistry Article/Essay

Abstract.

J. Eur. Ceram. Soc. 30 (2010) 1419-1425. (DOI: 10.1016/j.jeurceramsoc.2009.12.015).

DTA, XRD and sintering investigations of the system BaSnO3−BaGeO3, prepared by a mixed-oxide method, are described herein. The melting temperature of this system is about 1270 ± 5 °C. We find a partial solubility of BaGeO3 into BaSnO3 of the order of 6−7 mol%. Up to 50 mol% BaGeO3, the calcined powders (1150 °C) as well as the once-sintered samples consist of BaSnO3 and orthorhombic BaGeO3 at room temperature. A gradual appearance of hexagonal BaGeO3 can be observed in calcined powders and once-sintered ceramics with a BaGeO3 content above 50 mol%. After sintering at ³ 1200 °C for more than 1 h all ceramic bodies consist of BaSnO3 and sintering temperature and to a strong densification. Sintering at 1180 °C for 10 h and an addition of only 1 mol% BaGeO3 leads to dense ceramic bodies with cubic-like grains. orthorhombic BaGeO3. The addition of BaGeO3 leads to a considerable reduction of the