Sequence of structural transitions and electrocaloric properties in (Ba1-xCax)(Zr0.1Ti0.9)O-3 ceramics


Authors / Editors


Research Areas

No matching items found.


Publication Details

Output type: Chapter in book

UM6P affiliated Publication?: Yes

Author list: Kaddoussi, H.; Lahmar, A.; Gagou, Y.; Manoun, B.; Chotard, J. N.; Dellis, J. -L.; Kutnjak, Z.; Khemakhem, H.; Elouadi, B.; El Marssi, M.

Publication year: 2017

Volume number: 713

Start page: 164

End page: 179

Number of pages: 16

ISSN: 0925-8388

Languages: English (EN-GB)


View in Web of Science | View on publisher site | View citing articles in Web of Science


Abstract

The influence of the incorporation of Calcium in lead-free ferroelectric Ba(Zr0.1Ti0.9)O-3 perovskite on its structural phase transition, dielectric, pyroelectric, ferroelectric, and electrocaloric effect was investigated. Room temperature X-ray diffraction study allowed the identification of a continuous solid solution in the composition range 0 <= x <= 20 mol% with a rhombohedral to orthorhombic structural transition beyond 15mol%. Structural investigation of X-ray diffraction as a function of temperature reveals four different structural regions for the compositions with low content of Ca and three regions for the compositions with high Ca-content. Using heat flow measurements and dielectric investigations, two sequences of structural phase transitions were elucidated. The tetragonal-to- orthorhombic and orthorhombic-to-rhombohedral phase transitions induced by temperature variation were found to decrease with the increase of the Ca2+ content, while the cubic-to-tetragonal phase transition temperature remained almost unchanged and exhibited a dielectric permittivity maximum observed around the composition of x = 15mol%. The electrocaloric temperature change Delta T was calculated from two methods: the thermal variation of P-E hysteresis loops and pyroelectric current. The highest electrocaloric Delta T/DE = 0.24 K mm/kV was found for the composition x = 0.05. The largest electrocaloric responsivity around 0.30 K mm/kV was observed for this composition at Curie temperature using direct method. (C) 2017 Elsevier B.V. All rights reserved.


Keywords

No matching items found.


Documents

No matching items found.


Last updated on 2021-17-10 at 23:16