| Autor: |
David Gracia, Sara Lafuerza, Javier Blasco, Marco Evangelisti |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
APL Materials, Vol 11, Iss 12, Pp 121101-121101-8 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2166-532X |
| DOI: |
10.1063/5.0173585 |
| Popis: |
We report on the dielectric and electrocaloric properties of Ba1−yCayTi1−xHfxO3 for compositions 0.12 < x < 0.18 and y = 0.06, as well as x = 0.15 and 0 < y < 0.15, synthesized by the conventional solid-state reaction method. The addition of Hf/Ca broadens the ferroelectric-paraelectric phase transition while moving it toward room temperature. Two interferroelectric transitions are seen to converge, together with the ferroelectric–paraelectric phase transition, at ∼335 K for 0.12 < xc < 0.135 and y = 0.06. Consistent with the dielectric properties, the electrocaloric effect maximizes closer to room temperature with increasing Hf/Ca substitutions, which promote larger temperature spans. The electrocaloric responsivity gradually decreases from 0.2 to 0.1 K mm kV−1 with the addition of Hf/Ca. A homemade quasi-adiabatic calorimeter is employed to measure “directly” the electrocaloric data, which are also calculated from polarization-versus-electric-field cycles using “indirect” standard procedures. The comparison between measured and calculated values highlights the importance of having access to direct methods for a reliable determination of the electrocaloric effect. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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