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In this work, we fabricated a polycrystalline Tb2FeCrO6 double perovskite (DP) oxide by a solid-state reaction method and determined its structural, magnetic, and magnetocaloric (MC) properties. The Tb2FeCrO6 DP oxide was found to crystallize in a DP-type structure with the Pbnm space group and to undergo a paramagnetic-to-antiferromagnetic transition at a temperature of ~ 8.5 K. A large low-temperature MC effect was observed in the Tb2FeCrO6 DP oxide. The MC parameters in terms of maximum magnetic entropy changes, temperature-averaged entropy change (5 K), and relative cooling power for Tb2FeCrO6 DP oxide under a magnetic field change of 0–7 T were 12.9 J/kg K, 12.7 J/kg K, and 341.4 J/kg, respectively. These parameters were consistent with similarly high levels in recently updated MC materials, making the material a suitable candidate for low-temperature magnetic cooling applications. [ABSTRACT FROM AUTHOR]

The magnetic properties and magnetocaloric effect (MCE) in the ternary intermetallic compound of EuAuGe have been investigated. The compound undergoes a second-order magnetic phase transition at its own Curie temperatures T∼33 K. A large reversible table-like MCE has been observed from 1 to 40 K, which is related to the magnetic field-sensitive magnetic phase transition. For the magnetic field changes of 0-5 and 0-7 T, the maximum values of magnetic entropy change ( $-{\Delta } S_{\mathrm {M}}^{\max }$) are evaluated to be 7.6 and 10.1 J kg K, respectively; the corresponding relative cooling power ( RCP) are 358 and 499 J kg. The present results indicate that the EuAuGe compound is a considerable candidate for low-temperature refrigeration. [ABSTRACT FROM AUTHOR]

The magnetic and magnetocaloric properties in the equiatomic intermetallic compounds of TmZnAl and TmAgAl have been investigated. The compounds undergo a second order magnetic transition from paramagnetic to ferromagnetic state around its own Curie temperatures T C ∼2.8 K and 3.3 K for TmZnAl and TmAgAl, respectively. A considerable reversible magnetocaloric effect (MCE) was observed at low temperature. For a magnetic field change of 7 T, the maximum values of magnetic entropy change (−Δ S M max ) and relative cooling power ( RCP ) are 11.8 J/kg K and 289 J/kg for TmZnAl, respectively, and the corresponding values for TmAgAl are 14.1 J/kg K and 315 J/kg. [ABSTRACT FROM AUTHOR]

Magnetism and magnetocaloric effect in RE AgAl ( RE = Er and Ho) intermetallic compounds have been studied. Both compounds undergo a second order magnetic phase transition from paramagnetic to ferromagnetic state. A large reversible magnetocaloric effect was observed around its own Curie temperatures T C ∼ 14 and 18 K for ErAgAl and HoAgAl, respectively. For a field change of 0–7 T, the maximum magnetic entropy change reaches 13.7 and 13.8 J/kg K for RE = Er and Ho, respectively. The corresponding relative cooling powers are evaluated to be 398 and 525 J/kg. [ABSTRACT FROM AUTHOR]

In this study, two Mo 2 FeB 2 -type multiple rare-earth-containing MRE 2 Cu 2 In (MRE = Dy 1/3 Ho 1/3 Er 1/3 and Ho 1/3 Er 1/3 Tm 1/3 ; space group P 4/ mbm , No. 127) compounds are prepared via arc-melting method and systematically determined regarding their structural and magnetic properties, magnetic phase transition (MPT), and magnetocaloric (MC) performances. They undergo typical second-order MPT at low temperatures. The MC effect and MC performances of the present MRE 2 Cu 2 In compounds at low temperatures are assessed using magnetic entropy changes, refrigerant capacity, and temperature-averaged entropy changes. The values of these parameters are comparable to most updated candidate materials for low-temperature magnetic cooling, making the present MRE 2 Cu 2 In compounds considerable for practical applications. • The MRE 2 Cu 2 In (MRE = Dy 1/3 Ho 1/3 Er 1/3 and Ho 1/3 Er 1/3 Tm 1/3) compounds are fabricated. • The structural, magnetic, MPT and MC properties in MRE 2 Cu 2 In were studied. • These MRE 2 Cu 2 In compounds are considerable for cryogenic magnetic refrigeration. [ABSTRACT FROM AUTHOR]

• The gallides RE 2 Rh 3 Ga (RE = Gd, Dy, Ho, Er) compounds are fabricated. • The structural, MPT and magnetocaloric properties in RE 2 Rh 3 Ga were studied. • The present RE 2 Rh 3 Ga compound are considerable for cryogenic MR. We herein provide an experimental investigation of the gallides RE 2 Rh 3 Ga (RE = Gd, Dy, Ho, Er) regarding their magnetic properties and magnetocaloric effect (MCE). All of these RE 2 Rh 3 Ga intermetallic compounds crystallized with the Mg 2 Ni 3 Si type structure, space group R– 3 m and are ordered magnetically at low temperatures. Large reversible MCEs around their own ordering temperature were observed in all RE 2 Rh 3 Ga compounds and their magnetocaloric parameters including the maximum magnetic entropy change, refrigerant capacity, and temperature-averaged entropy change are comparable to those of some recently reported candidate materials with prominent performances, making them considerable for cryogenic MR applications. [ABSTRACT FROM AUTHOR]

• The RE 2 Ga 2 Mg (RE = Tm, Er, Ho) compounds were fabricated. • The magnetic and magnetocaloric properties were investigated. • Large conventional and inverse magnetocaloric effects were observed. • The Tm 2 Ga 2 Mg is considerable for cryogenic magnetic cooling. The Mo 2 FeB 2 -type compounds RE 2 Ga 2 Mg (RE = Tm, Er, Ho) (space group P 4/ mbm) exhibit a large magnetocaloric (MC) effect which makes them promising for use in cryogenic magnetic cooling applications. They exhibit low temperature metamagnetic nature below their Néel temperatures of 6.8, 11.7 and 18.4 K for Tm 2 Ga 2 Mg, Er 2 Ga 2 Mg and Ho 2 Ga 2 Mg, respectively. The magnetic entropy change, the temperature-averaged entropy change (3 K-lift), and the relative cooling power under a magnetic field change of 0–7 T are 15.6, 15.4 J/kgK and 275.8 J/kg for Tm 2 Ga 2 Mg; 13.2, 13.0 J/kgK and 268.0 J/kg for Er 2 Ga 2 Mg; as well as 9.1, 9.0 J/kgK and 223.0 J/kg for Ho 2 Ga 2 Mg, respectively. [ABSTRACT FROM AUTHOR]

In this work, polycrystalline oxides viz., Ho 2 CrMnO 6 (HCMO) and Er 2 CrMnO 6 (ECMO), were prepared using the sol-gel process, and their crystal structure, magnetic properties, and magnetocaloric effects (MCEs) were studied. X-ray refinement results demonstrate that both oxides exhibited the B -site disordered perovskite type structure (Pbnm space group). A ferromagnetic-paramagnetic phase transition as well as large reversible MCEs was also observed at Curie temperatures (T C) of ~6.1 and ~5.2 K for HCMO and ECMO, respectively. For a magnetic field change (ΔH) of 0–7 T, the maximum magnetic entropy change (-Δ S M), temperature-averaged entropy change (TEC 3), and relative cooling power (RCP) were estimated to be 11.03 J/kgK, 11.02 J/kgK, and 322.7 J/kg for HCMO, and 12.94 J/kgK, 12.80 J/kgK and 277.5 J/kg for ECMO. [ABSTRACT FROM AUTHOR]

Rare earth (RE) based RE - TM - X (TM = transition metal elements; X = P - block elements) materials have received continuous attention due to the exhibition of various intriguing magnetic functional characteristics. In this work, a combined experimental and theoretical investigation has been conducted in detail for RE Co 12 B 6 (RE = Ce, Pr, Nd) compounds with regard to their structural and magnetic properties, particularly the magnetocaloric effect and magnetic phase transition (MPT). All of the present RE Co 12 B 6 compounds are found to crystalize in the SrNi 12 B 6 -type structure and with a ferrimagnetic ground state, which is confirmed by density functional theory calculations and magnetization measurements. The magnetic moments of RE atoms and Co atoms tend to be in antiparallel alignment, and the MPT of these materials originates primarily from the spin-polarized 3 d electrons of the Co atoms, which can be greatly affected by the 4 f electrons of RE atoms. Considerable magnetocaloric effects have been observed around its own T C of 130, 157, and 160 K, for CeCo 12 B 6 , PrCo 12 B 6 , and NdCo 12 B 6 , respectively, which is related to a typical second-order MPT. The corresponding maximum magnetic entropy change and relative cooling power values,with field changes of 0–70 kOe, are determined to be 2.54, 2.84, and 2.77 J/kg K and 116.8, 156.2, and 155.1 J/kg, respectively. The MPT properties of present RE Co 12 B 6 compounds were studied in further detail by critical analysis using the modified Arrott Plot and Kouvel-Fisher methods, which can be explained within the frame of the 3D Heisenberg model with short-range magnetic interaction. [Display omitted] [ABSTRACT FROM AUTHOR]

• The magnetism and magnetocaloric effect (MCE) were investigated in Er 4 CoCd compound. • A large magnetocaloric effect in Er 4 CoCd compound was observed. • The origin of MCE and its potential application in Er 4 CoCd were discussed. The Er-based compound Er 4 CoCd was synthesized successfully and its structural, magnetic together with magnetocaloric properties were investigated in detail. The Er 4 CoCd crystallized in a Gd 4 RhIn-type structure with the space group of F 4 ¯ 3 m , which was confirmed by Rietveld refinement. A ferromagnetic transition was observed around its Curie temperature (T C) of 12.5 K accompanied by a large magnetocaloric effect (MCE). The performance of MCE for Er 4 CoCd was evaluated by the isothermal maximal magnetic entropy (- Δ S M max) , the temperature averaged entropy change (TEC) at 10 K temperature lift [ TEC (10 K)], and the relative cooling power (RCP). The values of - Δ S M max , TEC (10 K), and RCP of Er 4 CoCd are 20.4 J/kg K, 19.2 J/kg K, and 503 J/kg under the magnetic field change (Δ H) of 0–5 T, respectively. [ABSTRACT FROM AUTHOR]