Giant electrocaloric effect in PZT bilayer thin films by utilizing the electric field engineering

Organic and inorganic relaxor ferroelectrics used for electrocaloric effect (ECE) applications are introduced. Relaxor ferroelectrics offer several advantages for ECE devices, e.g., infinite states without applying electric field, field-induced large polarization, no-hysteresis of heating and cooling, small-hysteresis polarization loss, room temperature phase transition, and broad temperature range. The ECE in relaxor ferroelectrics under a high electric field can be described using a theory similar to that for first-order phase transition materials. Large ECE was observed directly in high-energy electron irradiated poly(vinylidene fluoride–trifluoroethylene) (P(VDF–TrFE)) 68/32 mol% copolymers, P(VDF–TrFE–CFE) (CFE-chlorofluoroethylene) 59.2/33.6/7.2 mol% terpolymers, P(VDF–TrFE–CFE)–P(VDF–CTFE) (CTFE-chlorotrifluoroethylene) 95/5 wt% terpolymer blended films, and (PbLa)(ZrTi)O3 (PLZT) ceramic thin films. ECE reported in Pb(Sc1/2Ta1/2)O3 (PST), Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT) thin films is also summarized. Finally, the perspective of ECE devices is illustrated.

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Adjustable giant negative electrocaloric effect in Pb1+xZrO3 thin films

10.21203/rs.3.rs-212950/v1 ◽

2021 ◽

Author(s):

Yi Ye ◽

Fengzhen Huang ◽

Lin Lei ◽

Lin Liu ◽

Shuo Yan ◽

...

Keyword(s):

Thin Films ◽

Electric Field ◽

Room Temperature ◽

Sol Gel ◽

Entropy Change ◽

Interface Layer ◽

Electrocaloric Effect ◽

Temperature Range ◽

Si Substrates ◽

Pb Concentration

Abstract Electrocaloric effect (ECE) driven by electric field is suitable for implementation of built-in cooling in electronic devices. However, most of the known electrocaloric materials show low adiabatic temperature change ( ) near room temperature and usually require high electric field. Here, the investigation of ECE in Pb 1+x ZrO 3 (x=0, 0.1, 0.15) thin films, which were prepared on Pt/Ti/SiO 2 /Si substrates by sol-gel method, reveals that both the magnitude and the present temperature range of can be controlled by Pb concentration. Through increasing the dosage of PbO, decreased lead vacancies and enhanced interface layer are induced, which postpone the transition from antiferroelectrics to ferroelectrics of PbZrO 3 films under a given electric field ( E ), which thus controls the appearance temperature range of negative ECE. As a result, large isothermal entropy change ( and are observed in the temperature range from 260 K to 494 K, depending on the applied electric field and Pb concentration. Giant ECE ( , ~0.054) at room temperature (303 K) is obtained in Pb 1.1 ZrO 3 films under 460 kV/cm. This result provides a convenient method for modulating ECE of PbZrO 3 -based materials and will benefit its applications in cooling devices.

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Nonlinear Optical and Charge Distribution Studies Probing Electric Field Effects in Polymer Thin Films for Second Order Nonlinear Optical Applications.

10.21236/ada315598 ◽

1996 ◽

Author(s):

Hilary L. Lackritz

Keyword(s):

Thin Films ◽

Electric Field ◽

Charge Distribution ◽

Nonlinear Optical ◽

Polymer Thin Films ◽

Second Order ◽

Electric Field Effects ◽

Optical Applications ◽

Distribution Studies ◽

Nonlinear Optical Applications

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Effect of the electric field in glow discharge plasma sheath on the optoelectronic properties of the AlxZn1-xO thin films

Optik ◽

10.1016/j.ijleo.2021.166772 ◽

2021 ◽

Vol 239 ◽

pp. 166772

Author(s):

A. Amini ◽

M.S. Zakerhamidi ◽

S. Khorram

Keyword(s):

Thin Films ◽

Glow Discharge ◽

Electric Field ◽

Discharge Plasma ◽

Optoelectronic Properties ◽

Plasma Sheath ◽

Glow Discharge Plasma

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Near Room‐Temperature Large Electrocaloric Effect in Barium Titanate Single Crystal Based on Electric Field‐Temperature Phase Diagram

physica status solidi (RRL) - Rapid Research Letters ◽

10.1002/pssr.202100251 ◽

2021 ◽

Author(s):

Junjie Li ◽

Zhonghua Li ◽

Jingjin He ◽

Yuxuan Hou ◽

Yanjing Su ◽

...

Keyword(s):

Phase Diagram ◽

Barium Titanate ◽

Electric Field ◽

Single Crystal ◽

Room Temperature ◽

Temperature Phase ◽

Electrocaloric Effect ◽

Field Temperature ◽

Temperature Phase Diagram

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Adjustable negative electrocaloric effect in Pb1+xZrO3 thin films

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-021-06462-9 ◽

2021 ◽

Author(s):

Yi Ye ◽

Fengzhen Huang ◽

Lin Lei ◽

Lin Liu ◽

Shuo Yan ◽

...

Keyword(s):

Thin Films ◽

Electrocaloric Effect

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Thickness-dependent electrocaloric effect in mixed-phase Pb 0.87 Ba 0.1 La 0.02 (Zr 0.6 Sn 0.33 Ti 0.07 )O 3 thin films

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2016.0056 ◽

2016 ◽

Vol 374 (2074) ◽

pp. 20160056 ◽

Cited By ~ 3

Author(s):

T. M. Correia ◽

Q. Zhang

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Phase Transitions ◽

Film Thickness ◽

Tetragonal Phase ◽

Sol Gel ◽

Breakdown Field ◽

Electrocaloric Effect ◽

Thickness Increase ◽

Higher Temperature

Full-perovskite Pb 0.87 Ba 0.1 La 0.02 (Zr 0.6 Sn 0.33 Ti 0.07 )O 3 (PBLZST) thin films were fabricated by a sol–gel method. These revealed both rhombohedral and tetragonal phases, as opposed to the full-tetragonal phase previously reported in ceramics. The fractions of tetragonal and rhombohedral phases are found to be strongly dependent on film thickness. The fraction of tetragonal grains increases with increasing film thickness, as the substrate constraint throughout the film decreases with film thickness. The maximum of the dielectric constant ( ε m ) and the corresponding temperature ( T m ) are thickness-dependent and dictated by the fraction of rhombohedral and tetragonal phase, with ε m reaching a minimum at 400 nm and T m shifting to higher temperature with increasing thickness. With the thickness increase, the breakdown field decreases, but field-induced antiferroelectric–ferroelectric ( E AFE−FE ) and ferroelectric–antiferroelectric ( E FE−AFE ) switch fields increase. The electrocaloric effect increases with increasing film thickness. This article is part of the themed issue ‘Taking the temperature of phase transitions in cool materials’.

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