Electrocaloric Behavior and Temperature‐Dependent Scaling of Dynamic Hysteresis of Ba_0.85Ca_0.15Ti_0.9Zr_0.1O₃ Ceramics

Abstract

This article presents electrocaloric effect in Ba 0.85 Ca 0.15 Ti 0.9 Zr 0.1 O 3 (BCTZO) using an indirect approach based on Maxwell's relations. The peak electrocaloric performance is found to be an adiabatic temperature change of 0.41 K with electrocaloric strength of 19 mK cm/kV and a heat carrying capacity of~0.17 J/g under an electric field of 0-21.5 kV/cm. The ferroelectric hysteresis scaling relations for coercive field (E C ), remnant polarization (P r ), and hysteresis area (<A>) as a function of temperature (T) are also systematically investigated. The power-law temperature exponents are obtained for all the hysteresis parameters. The scaling relations are established as E c / T À0.6584 , P r / T À1.59 , and <A> / T À1.01623 . The presented scaling relations are compared with those reported in the literature for other ferroelectric materials.

Phenomenological modeling of phase transitions and electrocaloric effect in Ba(Zr0.2Ti0.8)O3‐(Ba0.7Ca0.3)TiO3

“…The temperature dependence of Δ S and Δ T are displayed in Figures and , respectively. Experimental data are also shown for comparison. In Figure (A) we plot temperature dependence of Δ S calculated using Method I and the experimental data obtained from direct measurement .…”

“…Electrocaloric effect usually peaks around phase transition, so the operating temperature is suggested to be near Curie point T c . It is noted that direct and indirect EC measurements for BZT‐ x BCT show discrepancies about the dependence on electric field strength and composition. Several mechanisms for enhancing EC effect have been put forward, including the effects of tricritical point, MPB, and relaxor state .…”

Large‐Temperature‐Invariant and Electrocaloric Performance of Modified Barium Titanate for Solid‐State Refrigeration

“…A promising alternative lies with the use of large ferroic transitions in other material classes (ferroelastic, ferromagnetic, and ferroelectric) . The electrocaloric effects (ECEs) of ferroelectric materials have been explored extensively . This method has several advantages over other solid‐state refrigeration techniques such as magnetocaloric, elastocaloric, and barocaloric cooling techniques .…”

“…[4,[11][12][13][14] Thee lectrocalorice ffects (ECEs) of ferroelectric materials have been explored extensively. [11][12][13][14][15][16][17][18][19] This method has severala dvantageso ver others olid-state refrigerationt echniques such as magnetocaloric, elastocaloric, and barocaloric cooling techniques. [3,4,10] In spite of encouraging progress,s everalc ritical issues have hindered the practical application of electrocaloric-based refrigeration.…”

Pyroelectric performance of porous Ba0.85Sr0.15TiO3 ceramics

“…The pyroelectric materials are well‐known for their unique thermo‐electric conversion ability because these materials have very high sensitivity to temporal change in temperature and hence have huge market for sensors, detectors, and thermal imaging applications 1‐3. In this context, there are many ceramic materials which have been explored by various researchers/academic groups from past few decades which have proved to be useful in many pyroelectric applications to date .…”