The very sharp first-order phase transition in single-crystal BaTiO3 permits thermal changes to be driven by small electric fields. resulting giant electrocaloric strength could exploited future cooling devices that operate at high frequency.

Abstract Caloric effects are currently under intense study due to the prospect of environment-friendly cooling applications. Most research is centred on large magnetocaloric and electrocaloric effects, but former require magnetic fields that challenging generate economically latter electric can only be applied without breakdown in thin samples. Here we use small changes hydrostatic pressure drive giant inverse barocaloric near ferrielectric phase transition ammonium sulphate. We find...

We report on calorimetry under applied hydrostatic pressure and magnetic field at the antiferromagnetic (AFM)-ferromagnetic (FM) transition of Fe$_{49}$Rh$_{51}$. Results demonstrate existence a giant barocaloric effect in this alloy, new functional property that adds to magnetocaloric elastocaloric effects previously reported for alloy. All caloric originate from AFM/FM which encompasses changes volume, magnetization entropy. The strong sensitivity temperatures both confers alloy...

We report on calorimetric measurements under hydrostatic pressure that enabled us to determine the barocaloric effect in Gd5Si2Ge2. The values for entropy change moderate pressures compare favourably those corresponding magnetocaloric this compound. Entropy data are complemented with direct of adiabatic pressure-induced temperature change.

We have studied magnetocaloric properties of a Ni-Mn-In metamagnetic shape-memory alloy especially designed in order to display low thermal hysteresis. Magnetization and calorimetric measurements under magnetic field been used determine isothermal field-induced entropy changes. Results obtained indirectly from magnetization data, quasi-directly isofield measurements, directly runs are systematic agree well with each other. analyzed the reproducibility cycling direct measurements. Due...

We report on the adiabatic temperature changes (ΔT) associated with magnetocaloric and barocaloric effects in a Fe49Rh51 alloy. For effect, data derived from entropy curves are compared to direct thermometry measurements. The agreement between two sets of provides support estimation ΔT for which indirectly determined curves. Large values obtained at relatively low magnetic field (2 T) hydrostatic pressure (2.5 kbar). It is also shown that both exhibit good reproducibility upon cycling, over...

There is currently great interest in replacing the harmful volatile hydrofluorocarbon fluids used refrigeration and air-conditioning with solid materials that display magnetocaloric, electrocaloric or mechanocaloric effects. However, field-driven thermal changes all of these caloric fall short respect to their fluid counterparts. Here we show plastic crystals neopentylglycol (CH3)2C(CH2OH)2 unprecedentedly large pressure-driven near room temperature due molecular reconfiguration, are...

We report on compressive strain measurements in polycrystalline magnetic shape memory alloys aimed at determining the entropy change associated with their elastocaloric effect. It is shown that for a maximum applied stress of 100 MPa, stress-induced amounts to ΔS=21 J/kg K. This value compares well values reported nonmagnetic alloys, and it same order as those best giant magnetocaloric materials moderate fields.

Calorimetry under magnetic field has been used to study the inverse magnetocaloric effect in Ni-Co-Mn-Ga-In shape memory alloys. It is shown that energy dissipated during a complete transformation loop only represents small fraction (5% 7%) of latent heat martensitic transition. found entropy values obtained from isofield temperature scans agree well with those isothermal scans. The reproducibility studied measurements. Reproducible cycling have within interval bounded by start forward...

We use calorimetry to identify pressure-driven isothermal entropy changes in ceramic samples of the prototypical ferroelectric BaTiO3. Near structural phase transitions at ∼400 K (cubic-tetragonal) and ∼280 (tetragonal-orthorhombic), inverse barocaloric response differs sign magnitude from corresponding conventional electrocaloric response. The differences arise due decrease unit-cell volume on heating through transitions, whereas large volumetric thermal expansion either side transitions.

We report on the multicaloric response of ${\mathrm{Fe}}_{49}{\mathrm{Rh}}_{51}$ alloy under combined application hydrostatic pressure and magnetic field. Experimental data are complemented by a mean field model that takes into account interplay between structural degrees freedom. A large strength has been found for this alloy, it is shown suitable combination enables sign entropy change to be reversed thus effect can tuned from conventional inverse. It also an extended temperature window...

Hydrostatic pressure represents an inexpensive and practical method of driving caloric effects in brittle magnetocaloric materials, which display first-order magnetostructural phase transitions whose large latent heats are traditionally accessed using applied magnetic fields. Here, moderate changes hydrostatic used to drive giant reversible inverse barocaloric near room temperature the notoriously material MnCoGeB0.03 . The compare favorably with those observed materials that magnetic....

Abstract Multiferroic materials with strong coupling between different degrees of freedom are prone to exhibit giant multicaloric effects resulting from the application or removal diverse external fields. These a synergic response combined action two fields when monocaloric both conventional (or inverse), while non-synergic occurs one is and other inverse. In all cases, properties (isothermal entropy adiabatic temperature changes) do not result simple addition corresponding quantities...

Abstract Giant barocaloric effects were recently reported for spin-crossover materials. The volume change in these materials suggests that the transition can be influenced by uniaxial stress, and give rise to giant elastocaloric properties. However, no measurements of properties compounds have been so far. Here, we demonstrated existence associated with transition. We dissolved particles ([Fe(L) 2 ](BF 4 ) , [L=2,6di(pyrazol-1-yl)pyridine]) into a polymeric matrix. showed application tensile...

The unavoidable existence of thermal hysteresis in magnetocaloric materials with a first-order phase transition is one the central problems limiting their implementation cooling devices. Using minor loops, however, allows achieving significant cyclic effects even relatively large hysteresis. Here, we compare thermometric measurements adiabatic temperature change ΔTad and calorimetric isothermal entropy ΔST when moving loops driven by magnetic fields. Under cycling 2 T, Ni-Mn-In-Co Heusler...

We report giant reversible barocaloric effects in [(CH₃)₄N]Mn[N₃]₃ hybrid organic–inorganic perovskite, near its first-order cubic-monoclinic structural phase transition at <italic>T</italic>₀ ∼ 305 K.

Spin crossover (SCO) complexes have been shown to exhibit giant mechanocaloric effects. Due the change of magnetization at spin transition, they are also expected show magnetocaloric However, experimental studies on properties in SCOs scarce. Here, we studied response SCO complex [Fe(L)2](BF4)2, [L = 2,6-di(pyrazol-1-yl)pyridine] using pulsed magnetic fields. We that applying a field can induce partial transformation from low high state. directly measure adiabatic temperature for different...

Abstract We report on calorimetric measurements under hydrostatic pressure in a series of composition related metamagnetic shape memory alloys. show that alloys exhibit barocaloric effect whose magnitude compares well to the magnetocaloric exibited by this kind While is inverse, has been found be conventional. The values obtained for pressure‐induced entropy changes at moderate pressures are range those reported giant caloric materials.

Caloric properties rely on the reversible thermal response of a given material to changes induced by an applied field. In magnetic shape-memory materials, thanks strong interplay between magnetism and structure, caloric effects can be application both mechanical (stress) fields. The study such is expanding field research opening novel opportunities in solid state refrigeration energy harvesting applications. this paper we present overview art subject. After brief discussion thermodynamics...

We study the giant elastocaloric effect in a Cu–Zn–Al shape‐memory alloy by means of simultaneous calorimetry and dilatometry measurements under applied uniaxial compression which have been carried out with bespoke experimental setup. The output data allow unique quasidirect indirect characterization thermal response that provides accurate Δ S T values. report large |Δ | = 22 J K kg −1 , 12.3 K, RC 325 driven moderate changes 32.2 MPa, is comparable performance best magnetocaloric materials....

We have used differential scanning calorimetry and thermometry techniques under applied magnetic field compressive uniaxial stress to determine isothermal entropy adiabatic temperature changes that quantify the caloric effects associated with magnetostructural transition of an ${\mathrm{Fe}}_{49}{\mathrm{Rh}}_{51}$ alloy. It is found increases increasing while it decreases for tensile stress. This behavior gives rise a conventional elastocaloric effect stresses in contrast reported inverse...

We have studied the impact of demagnetizing fields on magnetocaloric effect commercial-grade gadolinium plates. Adiabatic temperature changes (ΔT) were measured for magnetic applied along parallel and perpendicular directions The differences in obtained ΔT values accounted by internal field due to effects. A combination calorimetric measurements under a thermometric has enabled us obtain Brayton cycles two different orientations. It been found that refrigerant capacity cycle working at 1.6 T...