20 results on '"Caloric effects"'
Search Results
2. Evaluation of Thermomechanical Properties in a 2D Rotational Elastocaloric Prototype: A Numerical Study for Enhanced Energy Efficiency
- Author
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Cirillo, Luca, Greco, Adriana, and Masselli, Claudia
- Published
- 2024
- Full Text
- View/download PDF
3. 新規機能性酸化物材料の創製.
- Author
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島川 祐一
- Subjects
MAGNETIC entropy ,THERMAL expansion ,LATENT heat ,ENERGY storage ,TRANSITION temperature ,LEAD ,MAGNETOCALORIC effects ,HEAT storage - Abstract
Transition-metal oxides show lots of interesting and useful properties. The wide variety of their crystal structures gives rise to various electronic structures, which lead to various chemical and physical properties. The author has been interested in such transition-metal oxides and is seeking new materials with novel functional properties. In this review article new functional properties found in A-site-ordered quadruple perovskite structure oxides with the unusually high-valence cations are highlighted. Negative thermal expansion was found in NdCu
3 Fe4 O12 at the intersite-charge-transfer transition temperature near room temperature. The property is useful for developing materials to compensate the normal positive thermal expansion. Significant latent heat was also found to be provided by the intersite-charge-transfer transition in NdCu3 Fe4 O12 . The large latent heat is considered to be related with unusual first-order magnetic entropy change induced by the charge transition. The large entropy change can be utilized for thermal control through a caloric effect, which can make effective energy systems for thermal energy storage and refrigeration. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
4. Electrocaloric and barocaloric effects in organic materials
- Author
-
Liu, Zipeng and Moya, Xavier
- Subjects
Barocaloric ,Caloric effects ,Electrocaloric ,Ferroelectric ,Ureasil - Abstract
Electrocaloric (EC) and barocaloric (BC) materials undergo reversible thermal changes in response to changes in applied electric field and pressure, respectively. These materials could potentially be exploited in novel solid-state cooling systems that may replace current vapour-compression systems, which are environmentally harmful, noisy, and relatively energy inefficient. In this work, I studied EC effect and BC effects in multicaloric organic materials, which promise large caloric effects near room temperature. The dissertation is structured as follows. Chapter 1 introduces the background for conventional refrigeration and traditional caloric materials. Chapter 2 then surveys the literature on EC materials and BC materials, as well as the literature on EC prototype devices. Chapter 3 reviews the experimental and modelling methods used for this work. These include sample preparation methods, dielectric spectroscopy and ferroelectric polarisation measurements, calorimetry and infrared imaging, dilatometry and Landau models. Chapter 4 describes the study of EC effects in two dabco-based organic salts, namely [Hdabco][BF4] and [AH][ReO4], where dabco is 1,4-diazabicyclo[2.2.2]octane and AH is a variant of dabco, 1-azabicyclo[2.2.1]heptanium. Experiments and modelling demonstrates that [Hdabco][BF4] shows giant EC effects (isothermal entropy change |∆S| = 15.5 J K-1 kg-1 for |∆E| = 12 kV cm-1) that are one order-of-magnitude larger than those observed in traditional EC oxides such as BaTiO3 (|∆S|= 2.1 J K-1 kg-1 for |∆E| = 4 kV cm-1). [AH][ReO4] shows smaller EC effect of |∆S|~ 7.5 J K-1 kg-1 for |∆E| = 11.2 kV cm-1, but displays better mechanical integrity and operates closer to room temperature. It is concluded that dabco-based organic salts exhibit promising performance due to their large EC effects, non-toxicity and great tunability via chemical alterations. However, electrical leakage and breakdown remains an important challenge to be overcome for their use as EC working bodies. Chapter 5 describes the study of BC effects in the aforementioned dabco-based organic salts. BC effects in these materials have the advantage to be driven using hydrostatic pressure instead of electric field, thus avoiding issues related to electrical leakage and breakdown. Three compositions were selected for BC studies, namely [Hdabco][BF4], [Hdabco][ClO4] and [Hdabco][ReO4]. Among these, [Hdabco][ClO4] shows the largest reversible BC effects, |∆S| = 73.2 J K-1 kg-1 for |∆p| = 1200 bar, which compare well with those reported in state-of-the-art BC materials. Notably, BC effects in [Hdabco][BF4] largely outperform EC effects in the same compound, thus demonstrating that pressure is a useful driving parameter for leaky organic ferroelectrics. Chapter 6 describes BC studies in ureasil polymeric materials. These compounds show large changes in entropy when transforming from liquid to solid. By exploiting a gelation method, the liquid to solid phase transition in these compounds is transformed to a gel-to-solid phase transition, which is desirable for some caloric applications. By driving these transitions using pressure, very large BC effects of |ΔS| = 263 J K−1 kg−1 for |∆p| = 1200 bar are found, which are similar to those observed in commercial vapour-compression refrigerants, e.g. R134a. Moreover, the studied polymers have other advantages, in terms of being stretchable, non-toxic, inexpensive and have great tunability of transitions temperatures. Finally, chapter 7 summarises the main results of this work and discusses interesting avenues for future work.
- Published
- 2022
- Full Text
- View/download PDF
5. Caloric effects in ferroic materials
- Author
-
Kim, Ji-Yeob and Moya, Xavier
- Subjects
Ferroic materials ,Caloric effects ,Strain-mediated ,Surface magnetism ,Ferroelectric polymer ,Perovskite ,Heusler alloy - Abstract
There has been much effort to develop next generation refrigeration systems that do not use harmful fluids. Magnetocaloric, electrocaloric and mechanocaloric materials have been studied independently as potential replacement of these fluids refrigerants but each has its own limitations. More recently, multicaloric materials that respond to multiple fields have been proposed in order to overcome individual limitations. Here, I studied three different multicaloric materials. The first study focused on extrinsic magnetocaloric effects in La0.7Ca0.3MnO3 (LCMO) driven using strain. LCMO's intrinsic caloric effect near its ferromagnetic transition is small (-1.2 J kg−1 K−1 T−1 ) [1]. Moya et al. have discovered that LCMO thin films grown on BaTiO3 (BTO) substrates can produce extrinsic magnetocaloric effects as large as -9 J kg−1 K−1 T−1, driven by a structural phase transition in the substrate, and strain-mediated feedback [2]. However, producing high-quality thin films can be challenging, and thin films do not provide large thermal mass for cooling. Here, LCMO || BTO core-shell particles with different compositions were investigated to see whether they present similar behaviour to the film-substrate heterostructures, while simultaneously providing larger thermal mass. The second study focused on surface magnetocaloric effect in near stoichiomet- ric Ni-Mn-Ga (NMG) thin films. NMG is interesting as its ferromagnetic transition is accompanied by a structural transition, producing large magnetocaloric effects that can be driven using magnetic field and/or stress. In this study, the surface magnetisation was studied on 200-nm-thick NMG thin films grown on MgO sub- strate. Previous studies have reported that magnetisation is suppressed at the surface in NMG thin films, therefore compromising their magnetocaloric perfor- mance. Here, we observed that suppression of the magnetisation can be avoided by optimising growth conditions. Furthermore, using synchrotron techniques, we confirmed the presence of the magnetostructural phase transition at the surface, thus demonstrating that the surface is magnetocalorically active. The third study focused on barocaloric effects in fluorinated ferroelectric poly- mers of polyvinylidene fluoride - co - trifluoroethylene (PVDF-TrFE) with different compositions. P(VDF-TrFE) polymers have been previously investigated for elec- trocalorics effects driven by electric fields; here their barocaloric performance on applying and removing pressure is studied. Other ferroelectric materials have been studied for their barocaloric effects, but their performance was limited due to brittleness, low transition temperature, or small entropy changes. PVDF-TrFE is interesting as it is ductile, inexpensive and a good electrocaloric material. Here, we achieved the maximum reversible entropy change (|∆S| = 221.86 J kg−1 K−1) and temperature change (|∆T | = 29.05 K) in PVDF-TrFE 20 and PVDF-TrFE 25, respec- tively, with a pressure change of 2.7 kbar. These are much larger than the values obtained from the electrocaloric effect. [1] C. M. Xiong, J. R. Sun, Y. F. Chen, B. G. Shen, J. Du, and Y. X. Li, "Relation between magnetic entropy and resistivity in La 0.67Ca0.33MnO3," IEEE Trans. Magn., vol. 41, no. 1 I, pp. 122-124, 2005. [2] X. Moya, L. E. Hueso, F. Maccherozzi, A. I. Tovstolytkin, D. I. Podyalovskii, C. Ducati, L. C. Phillips, M. Ghidini, O. Hovorka, A. Berger, M. E. Vickers, E. Defay, S. S. Dhesi, and N. D. Mathur, "Giant and reversible extrinsic magne- tocaloric effects in La0.7Ca0.3MnO3 films due to strain," Nat. Mater., vol. 12, no. 1, pp. 52-58, 2012.
- Published
- 2021
- Full Text
- View/download PDF
6. Thermodynamics of multicaloric effects in multiferroic materials: application to metamagnetic shape-memory alloys and ferrotoroidics
- Author
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Saxena, Avadh [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division]
- Published
- 2016
- Full Text
- View/download PDF
7. Quantification of electronic and magnetoelastic mechanisms of first-order magnetic phase transitions from first principles: application to caloric effects in La(Fe Si )13
- Author
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Eduardo Mendive Tapia, Christopher E Patrick, Tilmann Hickel, Jörg Neugebauer, and Julie B Staunton
- Subjects
caloric effects ,ab initio thermodynamics ,magnetoelastic coupling ,first-order magnetic phase transitions ,Production of electric energy or power. Powerplants. Central stations ,TK1001-1841 ,Renewable energy sources ,TJ807-830 - Abstract
$\mathrm{La}(\mathrm{Fe}_{x}\mathrm{Si}_{1-x})_{13}$ and derived quaternary compounds are well-known for their giant, tunable, magneto- and barocaloric responses around a first-order paramagnetic-ferromagnetic transition near room temperature with low hysteresis. Remarkably, such a transition shows a large spontaneous volume change together with itinerant electron metamagnetic features. While magnetovolume effects are well-established mechanisms driving first-order transitions, purely electronic sources have a long, subtle history and remain poorly understood. Here we apply a disordered local moment picture to quantify electronic and magnetoelastic effects at finite temperature in $\mathrm{La}(\mathrm{Fe}_{x}\mathrm{Si}_{1-x})_{13}$ from first-principles. We obtain results in very good agreement with experiment and demonstrate that the magnetoelastic coupling, rather than purely electronic mechanisms, drives the first-order character and causes at the same time a huge electronic entropy contribution to the caloric response.
- Published
- 2023
- Full Text
- View/download PDF
8. Phase transitions, baro- and piezocaloric effects in single crystal and ceramics of ferroelectric NH4HSeO4.
- Author
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Bondarev, Vitaliy S., Mikhaleva, Ekaterina A., Gorev, Mikhail V., Molokeev, Maxim S., Bogdanov, Evgeniy V., Cherepakhin, Alexander V., and Flerov, Igor N.
- Subjects
- *
FERROELECTRIC ceramics , *FERROELECTRIC crystals , *PHASE transitions , *SINGLE crystals , *THERMAL expansion , *RELAXOR ferroelectrics - Abstract
A study of heat capacity, thermal dilatation and sensitivity to hydrostatic and uniaxial pressure was carried out on single-crystal and ceramic samples of NH 4 HSeO 4. The main parameters of low-temperature successive phase transitions B 2 (T 1) ↔ incommensurate IC (T 2) ↔ ferroelectric P 1 (T 3) ↔ non-ferroelectric did not depend on the type of samples. The behavior of the volumetric strain and the results of direct measurements of T 3 (p) contributed to the resolution of the longstanding problem associated with the ambiguity of the sign of the corresponding volumetric baric coefficient. The role of thermal expansion anisotropy in the formation of the piezocaloric effect (PCE) near the ferroelectric phase transition at T 3 has been studied. Due to the strong difference in the linear baric coefficients, the main contribution to the barocaloric effect (BCE) comes from the inverse intensive and extensive PCE associated with the a- axis. Compared to a single crystal, ceramics demonstrate lower BCE values, which, however, exist in a wider temperature range, which leads to close values of integral caloric parameters. The strong decrease in both BCE and PCE at low-temperature transformations in NH 4 HSeO 4 compared to the ferroelectrics NH 4 HSO 4 and NH 4 NH 4 SO 4 is associated with a small change in entropy during three low-temperature phase transitions, ΣΔ S i = 2.52 J/mol∙K, which is a consequence of a high degree of structural ordering in selenate as a result of a high-temperature transformation at T 0 between the superionic and B 2 phases, accompanied by a giant change in entropy, Δ S 0 ≈ R ln21. [Display omitted] • Size/surface as well as anisotropy effect on thermal properties of NH 4 HSeO 4. • Gigantic entropy change associated with transformation to superionic phase. • Expansion of the temperature range of the ferroelectric phase under pressure. • Large piezocaloric effect at P 1↔paraelectric transition under very low pressure. • NH 4 HSeO 4 is a decent refrigerant for cooling devices with low heat dissipation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Comparative analysis of elastocaloric and barocaloric effects in single-crystal and ceramic ferroelectric (NH4)2SO4.
- Author
-
Mikhaleva, Ekaterina, Gorev, Mikhail, Bondarev, Vitaly, Bogdanov, Evgeny, and Flerov, Igor
- Subjects
- *
FERROELECTRIC ceramics , *PYROELECTRICITY , *AMMONIUM sulfate , *FERROELECTRIC crystals , *COMPARATIVE studies , *SINGLE crystals - Abstract
We report the influence of anisotropy and texture on elasto(ElCE)- and baro(BCE)-caloric effects in single-crystal and ceramic (NH 4) 2 SO 4. Inverse extensive and intensive ElCE in ceramics, (ΔS ElCE) cer = 87 J/kg·K; ΔT AD = - 11.6 K), as well as in a single crystal along the ferroelectric axis a , (ΔS ElCE) a = 115 J/kg·K; (ΔT AD) a = - 16 K, significantly exceed BCE, ΔS BCE = 75 J/kg·K; ΔT AD = - 9.8 K, even at low pressure ~ 0.3 GPa. Caloric parameters of ammonium sulphate are comparable with those for promising solid-state refrigerants. Image, graphical abstract [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
10. Caloric effects of quantum materials: An outlook
- Author
-
Mario S. Reis and Ning Ma
- Subjects
Caloric effects ,Quantum materials ,Graphene ,Quantum dots ,Frustrated magnets ,Physics ,QC1-999 - Abstract
Solid-state cooling is an emerging technology embracing cryogenic and near room temperature devices. For further developments of this machinery, prototypes and caloric materials must be optimized in order to obtain a better final result than the well-known competitors based on gas compression technology. Thus, researches on materials and prototype optimization have been intensively carried out; and the present mini-review will focus on materials, specifically on quantum materials. We comprehensively describe their ability to produce heat, such as the magneto- and barocaloric effects on graphene, as well as the enhanced caloric properties of graphene-based nanocomposite. Quantum dots and frustrated magnets are also reviewed, linked with their potential to produce heat under an external perturbation, such as magnetic field (magnetocaloric effect) or mechanical pressure (barocaloric effect). This work shows that quantum materials are special materials, with advanced and emerging features that can be explored for application in devices for solid-state cooling.
- Published
- 2020
- Full Text
- View/download PDF
11. Electrocaloric and barocaloric effects in organic materials
- Author
-
Liu, Zipeng
- Subjects
Caloric effects ,Barocaloric ,Electrocaloric ,Ureasil ,Ferroelectric - Abstract
Electrocaloric (EC) and barocaloric (BC) materials undergo reversible thermal changes in response to changes in applied electric field and pressure, respectively. These materials could potentially be exploited in novel solid-state cooling systems that may replace current vapour-compression systems, which are environmentally harmful, noisy, and relatively energy inefficient. In this work, I studied EC effect and BC effects in multicaloric organic materials, which promise large caloric effects near room temperature. The dissertation is structured as follows. Chapter 1 introduces the background for conventional refrigeration and traditional caloric materials. Chapter 2 then surveys the literature on EC materials and BC materials, as well as the literature on EC prototype devices. Chapter 3 reviews the experimental and modelling methods used for this work. These include sample preparation methods, dielectric spectroscopy and ferroelectric polarisation measurements, calorimetry and infrared imaging, dilatometry and Landau models. Chapter 4 describes the study of EC effects in two dabco-based organic salts, namely [Hdabco][BF4] and [AH][ReO4], where dabco is 1,4-diazabicyclo[2.2.2]octane and AH is a variant of dabco, 1-azabicyclo[2.2.1]heptanium. Experiments and modelling demonstrates that [Hdabco][BF4] shows giant EC effects (isothermal entropy change |∆S| = 15.5 J K-1 kg-1 for |∆E| = 12 kV cm-1) that are one order-of-magnitude larger than those observed in traditional EC oxides such as BaTiO3 (|∆S|= 2.1 J K-1 kg-1 for |∆E| = 4 kV cm-1). [AH][ReO4] shows smaller EC effect of |∆S|~ 7.5 J K-1 kg-1 for |∆E| = 11.2 kV cm-1, but displays better mechanical integrity and operates closer to room temperature. It is concluded that dabco-based organic salts exhibit promising performance due to their large EC effects, non-toxicity and great tunability via chemical alterations. However, electrical leakage and breakdown remains an important challenge to be overcome for their use as EC working bodies. Chapter 5 describes the study of BC effects in the aforementioned dabco-based organic salts. BC effects in these materials have the advantage to be driven using hydrostatic pressure instead of electric field, thus avoiding issues related to electrical leakage and breakdown. Three compositions were selected for BC studies, namely [Hdabco][BF4], [Hdabco][ClO4] and [Hdabco][ReO4]. Among these, [Hdabco][ClO4] shows the largest reversible BC effects, |∆S| = 73.2 J K-1 kg-1 for |∆p| = 1200 bar, which compare well with those reported in state-of-the-art BC materials. Notably, BC effects in [Hdabco][BF4] largely outperform EC effects in the same compound, thus demonstrating that pressure is a useful driving parameter for leaky organic ferroelectrics. Chapter 6 describes BC studies in ureasil polymeric materials. These compounds show large changes in entropy when transforming from liquid to solid. By exploiting a gelation method, the liquid to solid phase transition in these compounds is transformed to a gel-to-solid phase transition, which is desirable for some caloric applications. By driving these transitions using pressure, very large BC effects of |ΔS| = 263 J K−1 kg−1 for |∆p| = 1200 bar are found, which are similar to those observed in commercial vapour-compression refrigerants, e.g. R134a. Moreover, the studied polymers have other advantages, in terms of being stretchable, non-toxic, inexpensive and have great tunability of transitions temperatures. Finally, chapter 7 summarises the main results of this work and discusses interesting avenues for future work.
- Published
- 2023
- Full Text
- View/download PDF
12. Charge Transfer Induced Caloric Effects.
- Author
-
de Oliveira, Nilson A.
- Subjects
- *
ENTROPY , *CHARGE transfer , *ELECTRONS , *MAGNETIC fields , *SOLID state electronics - Abstract
In this paper, the entropy change and the caloric effects induced by charge transfer are discussed. According to the general discussion based on simple physical arguments in the framework of itinerant electrons, large caloric effects can be induced by the charge transfer mechanism even in non‐magnetic materials. This fact, which can be very important to build solid state refrigerators with high performance, opens a new horizon in this area of research. We also suggest some compounds which are good candidates to exhibit caloric effects induced by the physical mechanism of charge transfer in a wide range of temperatures. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
13. Innovative heating and cooling systems based on caloric effects:A review
- Author
-
Itard, Laure, Hensen-Centnerová, Lada, Boerstra, Atze, Bluyssen, Philomena, Hensen, Jan, Klein, Tillmann, Loomans, Marcel, Pauwels, Pieter, Struck, Christian, Tenpierik, Martin, Geldermans, Bob, Johra, Hicham, Bahl, Christian, Itard, Laure, Hensen-Centnerová, Lada, Boerstra, Atze, Bluyssen, Philomena, Hensen, Jan, Klein, Tillmann, Loomans, Marcel, Pauwels, Pieter, Struck, Christian, Tenpierik, Martin, Geldermans, Bob, Johra, Hicham, and Bahl, Christian
- Abstract
Heat pumps (HPs) are an excellent solution to supply heating and cooling for indoor space conditioning and domestic hot water (DHW) production. Conventional HPs are typically electrically driven and operate with a vapour-compression thermodynamic cycle of refrigerant fluid to transfer heat from a cold source to a warmer sink. This mature technology is cost-effective and achieves appreciable coefficients of performance (COP). The HP market demand is driven up by the urge to improve the energy efficiency of building heating systems coupled with the increase of global cooling needs for air-conditioning. Unfortunately, the refrigerants used in current conventional HPs can have large greenhouse or ozone-depletion effect. Alternative gaseous refrigerants have been identified but they present some issues regarding toxicity, flammability, explosivity, low energy efficiency or high cost. However, several non-vapour-compression HP technologies have been invented and could be promising alternatives to conventional systems, with potential for higher COP and without the aforementioned refrigerant drawbacks. Among those, the systems based on the so-called “caloric effects” of solid-state refrigerants are gaining a lot of attention. The caloric effects are large entropy and adiabatic temperature changes caused by the application or removal of an external field in certain specific solid materials. There are 4 main caloric effects: magnetocaloric, elastocaloric, electrocaloric and barocaloric. Each of them is characterized by the nature of the field and the response that induces the entropy and adiabatic temperature change: variation of the magnetic field, uniaxial mechanical stress, electrical field or hydrostatic pressure, respectively. A HP cycle can be based on these caloric effects and several heating/cooling prototypes were developed and tested over the last few decades. Although not mature technologies yet, some of these caloric systems are well suited to become new efficient
- Published
- 2022
14. Caloric effects in ferroic materials
- Author
-
Kim, Ji-Yeob
- Subjects
Strain-mediated ,Ferroic materials ,Heusler alloy ,Caloric effects ,Ferroelectric polymer ,Perovskite ,Surface magnetism - Abstract
There has been much effort to develop next generation refrigeration systems that do not use harmful fluids. Magnetocaloric, electrocaloric and mechanocaloric materials have been studied independently as potential replacement of these fluids refrigerants but each has its own limitations. More recently, multicaloric materials that respond to multiple fields have been proposed in order to overcome individual limitations. Here, I studied three different multicaloric materials. The first study focused on extrinsic magnetocaloric effects in La0.7Ca0.3MnO3 (LCMO) driven using strain. LCMO’s intrinsic caloric effect near its ferromagnetic transition is small (-1.2 J kg−1 K−1 T−1 ) [1]. Moya et al. have discovered that LCMO thin films grown on BaTiO3 (BTO) substrates can produce extrinsic magnetocaloric effects as large as -9 J kg−1 K−1 T−1, driven by a structural phase transition in the substrate, and strain-mediated feedback [2]. However, producing high-quality thin films can be challenging, and thin films do not provide large thermal mass for cooling. Here, LCMO || BTO core-shell particles with different compositions were investigated to see whether they present similar behaviour to the film-substrate heterostructures, while simultaneously providing larger thermal mass. The second study focused on surface magnetocaloric effect in near stoichiomet- ric Ni-Mn-Ga (NMG) thin films. NMG is interesting as its ferromagnetic transition is accompanied by a structural transition, producing large magnetocaloric effects that can be driven using magnetic field and/or stress. In this study, the surface magnetisation was studied on 200-nm-thick NMG thin films grown on MgO sub- strate. Previous studies have reported that magnetisation is suppressed at the surface in NMG thin films, therefore compromising their magnetocaloric perfor- mance. Here, we observed that suppression of the magnetisation can be avoided by optimising growth conditions. Furthermore, using synchrotron techniques, we confirmed the presence of the magnetostructural phase transition at the surface, thus demonstrating that the surface is magnetocalorically active. The third study focused on barocaloric effects in fluorinated ferroelectric poly- mers of polyvinylidene fluoride – co – trifluoroethylene (PVDF-TrFE) with different compositions. P(VDF-TrFE) polymers have been previously investigated for elec- trocalorics effects driven by electric fields; here their barocaloric performance on applying and removing pressure is studied. Other ferroelectric materials have been studied for their barocaloric effects, but their performance was limited due to brittleness, low transition temperature, or small entropy changes. PVDF-TrFE is interesting as it is ductile, inexpensive and a good electrocaloric material. Here, we achieved the maximum reversible entropy change (|∆S| = 221.86 J kg−1 K−1) and temperature change (|∆T | = 29.05 K) in PVDF-TrFE 20 and PVDF-TrFE 25, respec- tively, with a pressure change of 2.7 kbar. These are much larger than the values obtained from the electrocaloric effect. [1] C. M. Xiong, J. R. Sun, Y. F. Chen, B. G. Shen, J. Du, and Y. X. Li, “Relation between magnetic entropy and resistivity in La 0.67Ca0.33MnO3,” IEEE Trans. Magn., vol. 41, no. 1 I, pp. 122–124, 2005. [2] X. Moya, L. E. Hueso, F. Maccherozzi, A. I. Tovstolytkin, D. I. Podyalovskii, C. Ducati, L. C. Phillips, M. Ghidini, O. Hovorka, A. Berger, M. E. Vickers, E. Defay, S. S. Dhesi, and N. D. Mathur, “Giant and reversible extrinsic magne- tocaloric effects in La0.7Ca0.3MnO3 films due to strain,” Nat. Mater., vol. 12, no. 1, pp. 52–58, 2012.
- Published
- 2022
- Full Text
- View/download PDF
15. Innovative heating and cooling systems based on caloric effects:A review
- Author
-
Johra, Hicham, Bahl, Christian, Itard, Laure, Hensen-Centnerová, Lada, Boerstra, Atze, Bluyssen, Philomena, Hensen, Jan, Klein, Tillmann, Loomans, Marcel, Pauwels, Pieter, Struck, Christian, Tenpierik, Martin, and Geldermans, Bob
- Subjects
Heat pump ,Performance ,Barocaloric heat pump ,Non-vapour-compression heat pump alternatives ,Caloric effect ,Magnetocaloric heat pump ,Review ,Electrocaloric heat pump ,SDG 11 - Sustainable Cities and Communities ,Elastocaloric ,Magnetocaloric ,Caloric effects ,Innovative heat pump ,SDG 13 - Climate Action ,Barocaloric ,Electrocaloric ,Elastocaloric heat pump ,SDG 9 - Industry, Innovation, and Infrastructure ,SDG 7 - Affordable and Clean Energy ,SDG 12 - Responsible Consumption and Production - Abstract
Heat pumps (HPs) are an excellent solution to supply heating and cooling for indoor space conditioning and domestic hot water (DHW) production. Conventional HPs are typically electrically driven and operate with a vapour-compression thermodynamic cycle of refrigerant fluid to transfer heat from a cold source to a warmer sink. This mature technology is cost-effective and achieves appreciable coefficients of performance (COP). The HP market demand is driven up by the urge to improve the energy efficiency of building heating systems coupled with the increase of global cooling needs for air-conditioning. Unfortunately, the refrigerants used in current conventional HPs can have large greenhouse or ozone-depletion effect. Alternative gaseous refrigerants have been identified but they present some issues regarding toxicity, flammability, explosivity, low energy efficiency or high cost. However, several non-vapour-compression HP technologies have been invented and could be promising alternatives to conventional systems, with potential for higher COP and without the aforementioned refrigerant drawbacks. Among those, the systems based on the so-called “caloric effects” of solid-state refrigerants are gaining a lot of attention. The caloric effects are large entropy and adiabatic temperature changes caused by the application or removal of an external field in certain specific solid materials. There are 4 main caloric effects: magnetocaloric, elastocaloric, electrocaloric and barocaloric. Each of them is characterized by the nature of the field and the response that induces the entropy and adiabatic temperature change: variation of the magnetic field, uniaxial mechanical stress, electrical field or hydrostatic pressure, respectively. A HP cycle can be based on these caloric effects and several heating/cooling prototypes were developed and tested over the last few decades. Although not mature technologies yet, some of these caloric systems are well suited to become new efficient and sustainable solutions for indoor space conditioning and DHW production. This paper aims to raise awareness in the building community about these innovative caloric systems. It sheds some light on the recent progress in that field and compares the performance of caloric systems with that of conventional vapour-compression HPs for building applications.Presentation of this paper at the CLIMA 2022 conference can be found here: https://youtu.be/oAjfT2_HEYo
- Published
- 2022
16. Thermodynamics of multicaloric effects in multiferroic materials: application to metamagnetic shape-memory alloys and ferrotoroidics.
- Author
-
Planes, Antoni, Castán, Teresa, and Saxena, Avadh
- Subjects
- *
THERMODYNAMICS , *MULTIFERROIC materials , *FERROELECTRIC materials , *FERROMAGNETIC materials , *DIELECTRIC materials , *FERROELECTRICITY - Abstract
We develop a general thermodynamic framework to investigate multicaloric effects in multiferroic materials. This is applied to the study of both magnetostructural and magnetoelectric multiferroics. Landau models with appropriate interplay between the corresponding ferroic properties (order parameters) are proposed for metamagnetic shapememory and ferrotoroidic materials, which, respectively, belong to the two classes of multiferroics. For each ferroic property, caloric effects are quantified by the isothermal entropy change induced by the application of the corresponding thermodynamically conjugated field. The multicaloric effect is obtained as a function of the two relevant applied fields in each class of multiferroics. It is further shown that multicaloric effects comprise the corresponding contributions from caloric effects associated with each ferroic property and the cross-contribution arising from the interplay between these ferroic properties. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
17. Caloric effects of quantum materials: An outlook
- Author
-
Ning Ma and Mario S. Reis
- Subjects
Quantum materials ,Frustrated magnets ,Materials science ,Nanocomposite ,Quantum dots ,Graphene ,General Physics and Astronomy ,Caloric theory ,Engineering physics ,lcsh:QC1-999 ,Magnetic field ,law.invention ,Caloric effects ,Quantum dot ,law ,Magnet ,Magnetic refrigeration ,Quantum ,lcsh:Physics - Abstract
Solid-state cooling is an emerging technology embracing cryogenic and near room temperature devices. For further developments of this machinery, prototypes and caloric materials must be optimized in order to obtain a better final result than the well-known competitors based on gas compression technology. Thus, researches on materials and prototype optimization have been intensively carried out; and the present mini-review will focus on materials, specifically on quantum materials. We comprehensively describe their ability to produce heat, such as the magneto- and barocaloric effects on graphene, as well as the enhanced caloric properties of graphene-based nanocomposite. Quantum dots and frustrated magnets are also reviewed, linked with their potential to produce heat under an external perturbation, such as magnetic field (magnetocaloric effect) or mechanical pressure (barocaloric effect). This work shows that quantum materials are special materials, with advanced and emerging features that can be explored for application in devices for solid-state cooling.
- Published
- 2020
18. Comparison of elastocaloric effect of natural rubber with other caloric effects on different-scale cooling application cases
- Author
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Gael Sebald, Daniel Guyomar, Zhongjian Xie, Laboratoire de Génie Electrique et Ferroélectricité (LGEF), Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)
- Subjects
Solid-state cooling ,Materials science ,Cooling applications ,Energy Engineering and Power Technology ,02 engineering and technology ,7. Clean energy ,01 natural sciences ,Environmental protection ,Industrial and Manufacturing Engineering ,[SPI]Engineering Sciences [physics] ,Environmental issues ,Natural rubber ,Caloric effects ,0103 physical sciences ,Electrocaloric ,010306 general physics ,Process engineering ,Simulation ,Low costs ,Magnetocaloric effects ,business.industry ,Caloric theory ,Environmental technology ,021001 nanoscience & nanotechnology ,Environmentally friendly ,Magnetocaloric ,visual_art ,visual_art.visual_art_medium ,Intrinsic property ,0210 nano-technology ,business ,Cooling - Abstract
cited By 2; International audience; In the framework of solid-state cooling technologies, four kinds of caloric effects, i.e., magnetocaloric (MC), electrocaloric (EC), barocaloric (BC) and elastocaloric (eC) effects, have been compared from the viewpoint of environmental issues and application cases. This field is primarily developed with the intention of protecting the environment. Currently, alternative caloric materials (called “good” materials) with properties such as being environmentally friendly, low-cost and practicable (low stimulus field) need to be found. All current caloric effects/materials are investigated for the common objective of cooling. Due to the variety of stimuli and intrinsic properties (different caloric performances for different dimensions) of caloric materials, they can exhibit unique advantages for various application cases. A “good” caloric material for large-scale cooling application is still rare and requires more research. © 2016 Elsevier Ltd
- Published
- 2017
19. Caloric Effects in Perovskite Oxides.
- Author
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Barman, Abhisikta, Kar‐Narayan, Sohini, and Mukherjee, Devajyoti
- Subjects
OXIDES - Abstract
Perovskite oxides show an amazing diversity of electronic and magnetic properties along with a myriad of structural variants and phase transitions. Large thermal changes may be driven near the ferroic phase transitions in perovskite oxides using magnetic, electric, and stress fields to manipulate conjugate order parameters. The ensuing magnetocaloric, electrocaloric, and mechanocaloric effects can be utilized for environment‐friendly and high‐efficiency solid‐state cooling applications. In this review the details of these caloric effects in perovskite oxides both from a chronological perspective and from the viewpoint of the recent advances in multiple caloric phenomena are described. The authors highlight the role of interfaces in oxide thin films for the different caloric effects and address some of the outstanding challenges for the fundamental understanding and practical implementation of perovskite oxides in solid state refrigeration. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
20. Caloric Effects in Perovskite Oxides
- Author
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A. Barman, Sohini Kar-Narayan, Devajyoti Mukherjee, Kar-Narayan, S [0000-0002-8151-1616], and Apollo - University of Cambridge Repository
- Subjects
010302 applied physics ,caloric effects ,Materials science ,Mechanical Engineering ,solid-state refrigeration ,Caloric theory ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,interfaces ,Chemical engineering ,perovskite oxide ,thin films ,Mechanics of Materials ,0103 physical sciences ,Thin film ,0210 nano-technology ,Perovskite (structure) - Abstract
Perovskite oxides show an amazing diversity of electronic and magnetic properties along with a myriad of structural variants and phase transitions. Large thermal changes may be driven near the ferroic phase transitions in perovskite oxides using magnetic, electric and stress fields to manipulate conjugate order parameters. The ensuing magnetocaloric, electrocaloric and mechanocaloric effects can be utilized for environment-friendly and high-efficiency solid-state cooling applications. Here we describe the details of these caloric effects in perovskite oxides both from a chronological perspective and from the viewpoint of the recent advances in multiple caloric phenomena. We highlight the role of interfaces in oxide thin films for the different caloric effects and address some of the outstanding challenges for the fundamental understanding and practical implementation of perovskite oxides in solid state refrigeration.
- Full Text
- View/download PDF
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