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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]

Reported here is a systematical investigation on the crystal structure, magnetic properties and magnetocaloric (MC) effect of three rare earth (RE) molybdate RE 2 MoO 6 (RE = Dy, Tb and Gd) oxides. The X-ray powder diffraction and the morphology as examined using the scanning electron microscope indicate phase-pure and polycrystalline nature of these oxides. The temperature (2–100 K) and magnetic field (up to 5 T) dependence of the magnetic measurements determine the magnetic phase transition (MPT) and MC properties. All the present RE 2 MoO 6 oxides crystallize in a monoclinic structure belonging to C 2/ c space group with the antiferromagnetic ordering at low temperature. Moreover, the RE 2 MoO 6 oxides hold reasonable values of MC parameters including the maximum isothermal magnetic entropy change/temperature-averaged entropy change (2 K lift) and relative cooling power values have been evaluated with the magnetic change of 0–5 T, yielding 17.22 (17.08) J/kgK and 277.67 J/kg for Dy 2 MoO 6 , 17.03 (16.83) J/kgK and 261.12 J/kg for Tb 2 MoO 6 , as well as 27.68 (26.69) J/kgK and 228.14 J/kg for Gd 2 MoO 6 , respectively. These acceptable MC parameters make the present RE 2 MoO 6 oxides potential candidates for cryogenic magnetic refrigeration (MR). [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]

We herein fabricated two gadolinium-transition metal-based high entropy (HE) oxides of Gd(Mn 0.25 Fe 0.25 Al 0.25 Cr 0.25)O 3 [denoted as Gd(4 TM 0.25)O 3 ] and Gd(Mn 0.2 Fe 0.2 Al 0.2 Co 0.2 Ni 0.2)O 3 [denoted as Gd(5 TM 0.2)O 3 ] and determined their structural, magnetic, and magnetocaloric properties. Both of present HE oxides are found to crystallize in the single-phase perovskite-type orthorhombic structure with a homogeneous microstructure and exhibit prominent cryogenic magnetocaloric performances. The values of magnetic entropy change, refrigerant capacity, and temperature-averaged entropy change (6K-lift) under the magnetic field change of 0–7 T are estimated to be 20.34 J/kgK, 295.4 J/kg, and 19.56 J/kgK for Gd(4 TM 0.25)O 3 , and to be 22.45 J/kgK, 258.2 J/kg, and 20.79 J/kgK for Gd(5 TM 0.2)O 3 , respectively, which are comparable with recently reported candidate materials for practical magnetic cooling. These findings not only indicate potential applications of present perovskite-type Gd(4 TM 0.25)O 3 and Gd(5 TM 0.2)O 3 HE oxides, but also provide meaningful clues for exploring HE oxides with prominent cryogenic magnetocaloric performances. [ABSTRACT FROM AUTHOR]

We herein fabricated the (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In high-entropy (HE) compounds and systematically determined its structural, magnetic, and magnetocaloric properties. The (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound was found to crystalize in a tetragonal Mo 2 B 2 Fe type structure (P4/ mbm space group) and undergoes typical second order type magnetic transition. Large MCE and prominent cryogenic magnetocaloric performances were observed in (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound. The evaluated values of magnetic entropy change and refrigerant capacity of (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound under magnetic field change of 0–7 T are 17.1 J/kgK and 398.0 J/kg which are comparable with the reported candidate materials for cryogenic magnetic cooling, making the present (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound also considerable for practical applications. • The (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound was fabricated. • The structural, magnetic, MPT and MC properties were investigated. • The present HE compound is considerable for cryogenic magnetic cooling. [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 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]