Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5440335 | Journal of the European Ceramic Society | 2017 | 9 Pages |
Abstract
The (0.94-x)Bi0.5Na0.5TiO3-0.06BaTiO3-x(Sr0.7Bi0.2â¡0.1)TiO3 (BNT-BT-xSBT, 0 â¤Â x â¤Â 0.24) solid solution ceramics were synthesized via a conventional solid-state reaction method and the correlation of phase structure, piezoelectric, ferroelectric properties and electrocaloric effect (ECE) was investigated in detail. The ECE in lead-free BNT-BT-xSBT ceramics was measured directly using a home-made adiabatic calorimeter with maximum adiabatic temperature change ÎT = 0.4 K with x = 0.08 under the electric field E = 6 kV/mm at room temperature. The position of maximum ECE was found in the vicinity of nonergodic and ergodic phase boundary, where the maximum change in entropy occurs as a result of the field-induced phase transformation between the ergodic and long-range ferroelectric phase. Besides, the mechanism for the shift of ECE peak is discussed in detail. Finally, the temperature dependence of ECE for BNT-BT-xSBT (x = 0, 0.04 and 0.08) was also investigated. This work may present a guideline for designing BNT-based ferroelectric relaxor ceramics for EC cooling technologies.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Feng Li, Guorui Chen, Xing Liu, Jiwei Zhai, Bo Shen, Huarong Zeng, Shandong Li, Peng Li, Ke Yang, Haixue Yan,