Dielectric Properties of (Bi_1.3RE_0.2)ZnNb_1.5O₇ (RE = La, Pr, Nd, Sm, Eu, Y and Er) Ceramics

Abstract

The dielectric properties of (Bi_1.3RE_0.2)ZnNb_1.5O₇ ceramics with different rare earth ion substitution in A site were investigated. All the samples showed a pure cubic pyrochlore structure. With the decrease of the ionic radii of rare earth ion RE^{3 +}, the dielectric loss at room temperature kept the magnitude of 10⁻⁴ at 1 MHz, and the dielectric constant was in the range of 108 to 127 which was smaller than that of Bi_1.5ZnNb_1.5O₇. The temperature coefficient of dielectric constant was optimized by RE³⁺ substitution. In low temperature, all the samples showed the relaxation behavior and had a regular change.

Keywords:

• Bismuth zinc niobate ceramics
• substitution
• dielectric properties
• relaxation

Acknowledgments

This work was supported by the Ministry of Science and Technology of China through 973-project under grant 2002CB613302.