Low-frequency dielectric spectroscopy of BaTiO₃:Ce³⁺ ceramics

Abstract

Dielectric spectroscopy of BaTiO₃ (BT) doped with Ce³⁺ (BT:Ce³⁺) ceramics was performed at extended temperatures and in the low-frequency ranges. BT:Ce³⁺ displays decreasing values of all phase transition temperatures with increasing Ce³⁺ content. Permittivity versus temperature plots showed decreasing values with increasing frequency with low dispersion and shifting values of the Curie temperatures (T_c) towards high frequencies. Comparable values of losses for BT and BT:Ce³⁺ ceramics suggest good charge compensation. At low frequencies and higher temperatures, thermally activated mechanisms of conduction increase the loss values. With increasing frequency, the BT:Ce³⁺ system displays increased and shifted loss peaks up to T_c and decreasing values above T_c. The characteristic exponent of the modified Curie–Weiss law is higher than one. These figures suggest a relaxor-like behaviour of BT:Ce³⁺ ceramics for low Ce³⁺ content. Phase diagrams of BT:Ce³⁺ ceramics show a strong decrease of T_c for low Ce³⁺ content.

Keywords:

• cerium doped BaTiO₃
• dielectric spectroscopy
• relaxor
• phase diagram

Acknowledgements

The author is grateful to University of Bucharest for support and cooperation to achieve this study.

Disclosure statement

No potential conflict of interest was reported by the authors.