Abstract
The microscopic mechanisms of the negative electrocaloric effect (ECE) of the single-phase (1−x)(0.94Bi 1/2 Na 1/2 TiO 3 -0.06BaTiO 3 )-xBa 1/2 Sr 1/2 TiO 3 (BNT-BT-BST) perovskite solid solutions fabricated via the sol-gel technique are explored in this study. Dielectric and mechanical relaxation analyses are employed to investigate the ferroelectric and structural transitions of the samples. The electrocaloric properties of the samples were measured by thermodynamics Maxwell relations. The difference between the depolarization temperature (T d ) and the maximum dielectric constant temperature (T m ) was found to decrease with increasing BST content. Doping with BST stabilized the ferroelectric phase along with unifying the EC temperature changes (ΔT) to only negative values. The origin of the uniform negative ECE of BNT-BT-BST is discussed.
Original language | American English |
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Journal | Materials Science and Engineering Faculty Publications and Presentations |
State | Published - 1 Dec 2013 |
Keywords
- ceramics
- dielectric constant
- dielectrics
- doping
- electric fields
- ferrelectric phase transitions
- sodium
EGS Disciplines
- Materials Science and Engineering