Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1463854 | Ceramics International | 2008 | 4 Pages |
Abstract
Bi2O3-ZnO-Nb2O5-based pyrochlore ceramics are receiving increasing attention due to their excellent dielectric properties in the microwave frequency range. Site disorder at the pyrochlore A-site is well known for lone pair active cations like Bi3+ and is attributed as the reason for this material's high dielectric constant and tunability. Bismuth zinc niobate ((Bi1.5Zn0.5)(Nb1.5Zn0.5)O7) [BZN] ceramics are prepared by the conventional solid-state reactions. The relative permittivity (Ér) and the dielectric loss tangent (tan δ) of the BZN ceramics sintered at 1000 °C are found to be around 130 and 0.0004, respectively at a frequency of 1 MHz measured at room temperature. The impedance spectroscopy measurements are conducted at different temperatures to separate grain and grain boundary contributions to the dielectric constant. The tunability of these ceramics is studied under a constant dc bias voltage.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
K. Sudheendran, K.C. James Raju,