Influence of Ni content on structural, magnetocaloric and electrical properties in manganite La 0.6 Ba 0.2 Sr 0.2 Mn 1- x Ni x O 3 (0 ≤ x ≤ 0.1) type perovskites.

Autor: Dhahri A; Laboratoire de Physique Appliquée, Faculté des Sciences de Sfax, Université de Sfax BP 1171 3000 Tunisia dhahridhahri14@gmail.com.; Department of Physics, College of Science and Humanities - Dawadmi, Shaqra University Riyadh Saudi Arabia., Laifi J; Physics Department, College of Science, Jouf University P.O. Box: 2014 Sakaka Saudi Arabia., Gouadria S; Department of Physics, College of Science, Princess Nourah Bint Abdulrahman University P.O. Box 84428 Riyadh 11671 Saudi Arabia., Elhadi M; Department of Physics, College of Science and Humanities - Dawadmi, Shaqra University Riyadh Saudi Arabia., Dhahri E; Laboratoire de Physique Appliquée, Faculté des Sciences de Sfax, Université de Sfax BP 1171 3000 Tunisia dhahridhahri14@gmail.com., Hlil EK; Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel 38000 Grenoble France.
Jazyk: angličtina
Zdroj: RSC advances [RSC Adv] 2022 Feb 01; Vol. 12 (7), pp. 3935-3947. Date of Electronic Publication: 2022 Feb 01 (Print Publication: 2022).
DOI: 10.1039/d1ra07059b
Abstrakt: We present a detailed study on the physical properties of La 0.6 Ba 0.2 Sr 0.2 Mn 1- x Ni x O 3 samples ( x = 0.00, 0.05 and 0.1). The ceramics were fabricated using the sol-gel route. Structural refinement, employing the Rietveld method, disclosed a rhombohedral R 3̄ c phase. The magnetization vs. temperature plots show a paramagnetic-ferromagnetic (PM-FM) transition phase at the T C (Curie temperature), which decreases from 354 K to 301 K. From the Arrott diagrams M 2 vs. μ 0 H / M , we can conclude the phase transition is of the second order. Based on measurements of the isothermal magnetization around T C , the magnetocaloric effects (MCEs) have been calculated. The entropy maximum change (-Δ S M ) values are 7.40 J kg -1 K -1 , 5.6 J kg -1 K -1 and 4.48 J kg -1 K -1 , whereas the relative cooling power (RCP) values are 232 J kg -1 , 230 J kg -1 and 156 J kg -1 for x = 0.00, 0.05 and 0.10, respectively, under an external field ( μ 0 H ) of 5 T. Through these results, the La 0.6 Ba 0.2 Sr 0.2 Mn 1- x Ni x O 3 (0 ≤ x ≤ 0.1) samples can be suggested for use in magnetic refrigeration technology above room temperature. The electrical resistivity ( ρ ) vs. temperature plots exhibit a transition from metallic behavior to semiconductor behavior in the vicinity of T M-SC . The adiabatic small polaron hopping (ASPH) model is applied in the PM-semiconducting part ( T > T MS ). Throughout the temperature range, ρ is adjusted by the percolation model. This model is based on the phase segregation of FM-metal clusters and PM-insulating regions.
Competing Interests: There are no conflicts to declare.
(This journal is © The Royal Society of Chemistry.)
Databáze: MEDLINE
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