Prospects and challenges of the electrocaloric phenomenon in ferroelectric ceramics

The electrocaloric effect (ECE), which refers to changes in the temperature of a material when an electric field is applied to or removed from the material, is one of the key phenomena of future highly efficient solid-state refrigeration devices.

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The Electrocaloric Effect in BaTiO3 Thick Film Multilayer Structure at High Electric Field

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.1304 ◽

2012 ◽

Vol 512-515 ◽

pp. 1304-1307 ◽

Cited By ~ 3

Author(s):

Yang Bai ◽

Kai Ding ◽

Guang Ping Zheng ◽

San Qiang Shi ◽

Lie Jie Qiao ◽

...

Keyword(s):

Electric Field ◽

Thick Film ◽

Temperature Change ◽

Multilayer Structure ◽

Tape Casting ◽

Adiabatic Temperature ◽

Ferroelectric Ceramics ◽

Heat Absorption ◽

Electrocaloric Effect ◽

Adiabatic Temperature Change

We demonstrated the superior electrocaloric effect (ECE) in BaTiO3 multilayer structure. The sample fabricated by tape-casting process has 120 effective ferroelectric layers with average layer thickness of 1.7 μm. The ferroelectric hysteresis loops were measured in the temperature range from 30 to 180 oC, and then the temperature dependences of ECE adiabatic temperature change and heat absorption were obtained according to Maxwell relation. A peak ECE adiabatic temperature change of 0.027 K/V and heat absorption of 0.36 J/g were observed near the ferroelectric phase transition at 125 oC under Vmax=25 V. The BaTiO3 thick film can sustain an external electric field (>500 kV/cm) several times higher than bulk ferroelectric ceramics (~30 kV/cm). Although the EC coefficient of BaTiO3 is much lower than lead-based ferroelectric ceramics, the ultrahigh working electric field endows it a large ECE, higher than that of most reported lead-based ferroelectric ceramics. In addition, the lead-free composition provides it a promising future in solid-state cooling technology.

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Enhanced Energy Storage Density and Excellent Thermal Stability Under Low Electric Fields of KF-added BNT–ST-AN Relaxor Ferroelectric Ceramics Prepared by the Solid-state Combustion Technique

10.21203/rs.3.rs-1159872/v1 ◽

2021 ◽

Author(s):

Chittakorn Kornphom ◽

Kamonporn Saenkam ◽

Theerachai Bongkarn

Keyword(s):

Grain Size ◽

Energy Storage ◽

Solid State ◽

Electric Field ◽

Ferroelectric Ceramics ◽

Energy Storage Density ◽

Excellent Thermal Stability ◽

Storage Density ◽

Wide Range ◽

Combustion Technique

Abstract Homogeneous 0.722(Bi0.5Na0.5TiO3)-0.228(SrTiO3)-0.05(AgNbO3) (BNT-ST-AN) ceramics with various amounts of potassium fluoride (KF) added were prepared by the solid-state combustion technique. The ceramics presented a single perovskite phase with coexisting rhombohedral (R), cubic (C) and orthorhombic (O) phases. The amount of the R phase decreased while the percentage of the C+O phase increased when KF addition increased from 0.0 to 3.0 mol%. The smallest grain size, the highest density and maximum dielectric constant (em) were achieved with a KF addition of 1.5 mol%. Following this design composition of the ceramics, the highest recoverable energy-storage density (Wrec ~1.60 J/cm3) and η above 85.8% at a low electric field (100 kV/cm) were obtained from BNT-ST-AN with KF addition at 1.5 mol% because this composition contained a morphotropic phase boundary (MPB) region and had the smallest grain size, which gave the lowest remnant polarization (Pr) and a large maximum polarization (Pm). Additionally, BNT-ST-AN with KF addition at 0.15 mol% exhibits stability over a wide range of temperatures (25–150°C) at a low electric field (100 kV/cm), which shows great potential in pulse-power system applications.

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Tunability of the dielectric constant of Ba0.1Sr0.9TiO3 ceramics in the paraelectric state

Journal of Materials Research ◽

10.1557/jmr.1995.1411 ◽

1995 ◽

Vol 10 (6) ◽

pp. 1411-1417 ◽

Cited By ~ 41

Author(s):

Abdelkader Outzourhit ◽

John U. Trefny ◽

Tomoko Kito ◽

Baki Yarar

Keyword(s):

Dielectric Constant ◽

Solid State ◽

Electric Field ◽

Solid State Reaction ◽

Paraelectric Phase ◽

Solid State Reaction Method ◽

Dielectric Constants ◽

Ferroelectric Ceramics ◽

Reaction Method ◽

Paraelectric State

Ba1−xSrxTiO3 (x = 0.9) ferroelectric ceramics were prepared successfully using a new wet technique and their structure and dielectric properties compared with those synthesized by the solid-state reaction method. The voltage dependence of the dielectric constant in the paraelectric phase was examined. It was found that the dielectric constants of these materials, prepared by both methods, exhibit large changes with applied voltage in the paraelectric phase. Tunability (the percentage change of the dielectric constant from its zero-bias value in the presence of a de-biasing electric field) was observed to exceed 30% at only 1.7 kV/cm at 77 K in the samples prepared by the solid-state reaction method. The tunability was found to decrease dramatically as the operating temperatures increased above the Curie point. These observations are interpreted in light of an existing phenomenological theory. The dependence of the dielectric constant in the paraelectric state upon a de-biasing electric field is also demonstrated as a potential method for the characterization of dielectric nonuniformities in ferroelectric ceramics.

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Large electrocaloric response and energy storage study in environmentally friendly (1 − x)K0.5Na0.5NbO3–xLaNbO3 nanocrystalline ceramics

Sustainable Energy & Fuels ◽

10.1039/c8se00276b ◽

2018 ◽

Vol 2 (12) ◽

pp. 2698-2704 ◽

Cited By ~ 7

Author(s):

Raju Kumar ◽

Ashish Kumar ◽

Satyendra Singh

Keyword(s):

Energy Storage ◽

Solid State ◽

Electric Field ◽

Environmentally Friendly ◽

High Potential ◽

Potential Candidate ◽

Electrocaloric Effect ◽

Nanocrystalline Ceramics ◽

Storage Study

An electrocaloric material with a negative and positive electrocaloric effect (ECE) is identified to be a high potential candidate for solid-state refrigeration technology due to a changing dipolar entropy under a varying electric field.

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Highly Efficient Ionic Gating of Solid-State Nanosensors by the Reversible Interaction between Pillar[6]arene-AuNPs and Azobenzene

Analytical Chemistry ◽

10.1021/acs.analchem.0c05241 ◽

2021 ◽

Vol 93 (6) ◽

pp. 3280-3286

Author(s):

Ruiping Zhang ◽

Jinmei Huang ◽

Kai Chen ◽

Imene Boussouar ◽

Xiaoya Chen ◽

...

Keyword(s):

Solid State ◽

Highly Efficient

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Electric-Field Effects on Reactions Between Oxides

MRS Proceedings ◽

10.1557/proc-481-303 ◽

1997 ◽

Vol 481 ◽

Author(s):

Matthew T. Johnson ◽

Shelley R. Gilliss ◽

C. Barry Carter

Keyword(s):

Solid State ◽

Electric Field ◽

Elevated Temperatures ◽

Ionic Current ◽

Reaction Rates ◽

Solid State Reactions ◽

Interfacial Stability ◽

Electric Field Effects ◽

Thin Film Diffusion ◽

Microscopy Techniques

ABSTRACTThin films of In2O3 and Fe2O3 have been deposited on (001) MgO using pulsed-laser deposition (PLD). These thin-film diffusion couples were then reacted in an applied electric field at elevated temperatures. In this type of solid-state reaction, both the reaction rate and the interfacial stability are affected by the transport properties of the reacting ions. The electric field provides a very large external driving force that influences the diffusion of the cations in the constitutive layers. This induced ionic current causes changes in the reaction rates, interfacial stability and distribution of the phases. Through the use of electron microscopy techniques the reaction kinetics and interface morphology have been investigated in these spinel-forming systems, to gain a better understanding of the influence of an electric field on solid-state reactions.

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