Impact of polymeric precursor and auto-combustion on the structural, microstructural, magnetic, and magnetocaloric properties of La0.8Sr0.2MnO3

• Published in: Journal of magnetism and magnetic materials Vol. 586; p. 171225
• Main Authors: Lakouader, Afaak, Hadouch, Youness, Mezzane, Daoud, Laguta, Valentin, Amjoud, M'barek, Dolocan, Voicu O., Novak, Nikola, Hajji, Lahoucine, Hassan Choukri, El, Razumnaya, Anna, Alimoussa, Abdelhadi, Kutnjak, Zdravko, Luk'yanchuk, Igor A., El Marssi, Mimoun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-11-2023; Elsevier
• Subjects: 3D Heisenberg model; Auto-combustion; Condensed Matter; Ferromagnetic; Magnetocaloric effect; Manganite; Mean-field model; Pechini; Physics; Manganite; Auto-combustion; Magnetocaloric effect; Pechini; Mean-field model; 3D Heisenberg model; Ferromagnetic
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2023.171225

•LSMO-AC and LSMO-PC crystallized in mixed phases with R-3c and Pbnm symmetries.•LSMO-AC and LSMO-PC samples are close to conventional universality class.•LSMO-PC, with porous surface, allows faster heat exchange.•LSMO-AC displays very high thermal stability of both ΔTM and ΔSM.
In this work, La0.8Sr0.2MnO3 (LSMO) nanopowders are synthesized using two different methods: Pechini (LSMO-PC) and auto-combustion (LSMO-AC). Nanoparticle sizes, structural, magnetic, and magnetocaloric properties were determined and compared. The X-ray diffraction confirms the coexistence of two phases; rhombohedral symmetry with space group R-3c and orthorhombic symmetry with space group Pbnm. The rhombohedral phase is dominant. The scanning electron microscope images show that LSMO-PC has larger nanoparticle sizes (∼495 nm) than LSMO-AC (∼195 nm). The samples exhibit ferromagnetic properties with distinct hysteresis loops and Curie temperatures of 340 K and 290 K for LSMO-PC and LSMO-AC, respectively. The variation of the magnetic entropy was measured indirectly using the Maxwell approach with increasing magnetic field. For LSMO-PC it reaches a maximum -ΔSM = 1.69 J/kg.K at 340 K and ΔH = 5 T. The associated adiabatic temperature change ΔTM is 1.04 K. While LSMO-PC demonstrates superior magnetic and magnetocaloric properties, LSMO-AC displays significant magnetocaloric thermal stability. The obtained values make LSMO-PC and LSMO-AC promising candidates for eco-friendly room-temperature magnetocaloric applications.