Analysis of the magnetic and magnetocaloric properties of ALaFeMnO6 (A = Sr, Ba, and Ca) double perovskites

Abstract

In previous studies, we have reported that double perovskiteLa NiMnO (LNMO) presents a non-negligible potential for room temperature magnetocaloric tasks. With the aim of improving even further the cooling performances and the working temperature range of double perovskites, we report the magnetic and magnetocaloric properties of La MnFeO and related compounds. The partial substitution of strontium for lanthanum enables us to cover a wide operating temperature range with significant magnetic entropy change extending beyond 300 K. For some optimal growth conditions, the entropy change varies slowly over an unusually large temperature range, which is of clear interest from a practical point of view.

Synergistic Effect of Reduced Graphene Oxide and BaLaMnFeO6 in BaLaMnFeO6/rGO Composite on Electrochemical Behavior

“…The lattice parameters have been estimated as a = 5.59 Å, b = 5.59 Å and c = 13.60 Å. [ 22 ] Figure a displays the measured X‐ray diffraction (XRD) pattern with Rietveld refinement of calcined pristine BLMFO. In addition to BLMFO peaks, minor traces of impurity peaks were observed, which could be attributed to the formation of metal oxides such as BaCO 3 and La 2 O 3 ; shown as rectangle and circle, respectively (Figure 1a,b).…”

Giant exchange bias effect in Ruddlesden-Popper oxides SrLaFe0.25+xMn0.25Co0.5−xK1, Das2, Lekshmi3 et al. 2020Phys. Rev. B10000View full textAdd to dashboardCite

“…However, the cluster glass transition at a comparatively higher temperature (T 1 = 43 K) in FMC2 along with its ZFC and FC bifurcation (T < T 2 ) under lower applied field points to the existence of fairly strong competing AFM-FM interactions even above T 1 in FMC2. Such a peculiar magnetic feature observed in FMC2 might be due to the existence of more Fe-rich regions with AFM (Fe 3+ -O-Fe 3+ and Fe 3+ -O-Mn 3+ ) and FM (Fe 3+ -O-Mn 4+ ) interactions, which usually exhibit magnetic ordering at higher temperatures [40,58,59]. Such strong AFM-FM competing interactions are absent above T 1 in FMC1 due to dominant Co-rich regions, where the corresponding superexchange interactions may lead to the formation of a spin glass state at low temperature [34].…”

Anomalous magnetic and electrical properties of disordered double perovskite alloy LaCaMnFeO6

“…Furthermore, recent researches have shown the effect of ion substitutions at both A-site and/or B-site on the physical properties of La 2 MnFeO 6 DP [19][20][21]. These substitutions typically induce distortions in the crystal structure, modify the charge state of Fe and Mn ions, and, consequently, alter the balance between magnetic interactions within the materials [19].…”