Effect of bismuth doping on structural, morphological, Griffiths-like phase, and magnetocaloric properties in La0.9−xBixBa0.1MnO3 (x = 0, 0.05, and 0.1)

• Published in: Journal of magnetism and magnetic materials Vol. 591; p. 171731
• Main Authors: Singh, Gurmeet, Gaur, Arpit, Bisht, Priyanka, Mahato, Rabindra Nath
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-02-2024
• Subjects: Curie-Weiss law; Griffiths phase; Magnetic materials; Phase transitions; Sol-gel method; Magnetic materials; Sol-gel method; Phase transitions; Griffiths phase; Curie-Weiss law
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2024.171731

•We have synthesized La0.9−xBixBa0.1MnO3 (x = 0, 0.05, 0.1) nanocrystalline samples successfully by using Sol-gel method and all the samples crystallize in orthorhombic phase with Pnma space group.•TEM analysis has shown that our samples have particle size in nanometer range (<100 nm).•Presence of short-range ferromagnetic clusters above TC evident from the sharp downturn and non-linearity observed in the inverse susceptibility close to critical temperature TC in the paramagnetic region.•Strong Griffiths like singularity determined from the deviation of linear Curie-Weiss behavior in the paramagnetic regime of nanocrystalline La0.9−xBixBa0.1MnO3 (x = 0, 0.05, and 0.1).•The Arrott plots show second-order magnetic phase transition for La0.9−xBixBa0.1MnO3 (x = 0.05, 0.1) and large values of magnetic cooling capacity have been found for a maximum field change of 5 T.
In this recent work, we have carried out the structural, morphological, Griffiths-like phase, and magneto-caloric studies of sol–gel-synthesized, nanocrystalline manganite La0.9−xBixBa0.1MnO3 (x = 0, 0.05, and 0.1). The Rietveld analysis of X-ray diffraction patterns of nanocrystalline La0.9−xBixBa0.1MnO3 (x = 0, 0.05, and 0.1) confirm the single-phase nature and orthorhombic crystal structure with Pnma space group for all samples. The images acquired with a transmission electron microscope reveal the average particle sizes ranges from 32 nm to 65 nm. The temperature-dependent magnetization measurements, for 0.05 T external applied magnetic field, have revealed paramagnetic (PM) to ferromagnetic (FM) phase transition with transition temperatures (TC) ∼ 228 K, 219 K, and 233 K for x  = 0, 0.05, and 0.1, respectively. The downward divergence of temperature dependence inverse susceptibility from the Curie-Weiss fit, indicates a pronounced Griffiths singularity in the samples. The positive slopes of Arrott plots for nanocrystalline La0.9−xBixBa0.1MnO3 (x = 0.05, 0.1) confirm the second-order magnetic phase transition. We have estimated the magnetic entropy change at different values of applied magnetic field for nanocrystalline La0.9−xBixBa0.1MnO3 (x = 0.05, 0.1) samples. Further, using this magnetic entropy data, we have also estimated the magnetic cooling capacity.