Ceramics-Silikáty 53, (4) 231 - 236 (2009)

Fabrication of single phase Ba₂Ti₉O₂₀ ceramic using the solid state reaction method is rather difficult due to thermodynamically various stable compounds that form in the vicinity of Ba₂Ti₉O₂₀ composition. In this study, microwave dielectric Ba₂Ti₉O₂₀ ceramic was successfully prepared by a polymerized complex method where crystallization of Ba₂Ti₉O₂₀ occurred from an amorphous polymeric mixture. Calcined powders had a particle size ranging from 10 to 50 nm with spherical shape. Single phase Ba₂Ti₉O₂₀ ceramic was obtained at 1200°C. The dielectric constant of Ba₂Ti₉O₂₀ ceramics at room temperature was around 34.5 at frequencies above 250 kHz but it significantly decreased when temperature was above 25°C.