Magnetism of Al2O3 matrix containing La0.5Ca0.5MnO3 particles

• Published in: Journal of alloys and compounds 2024-11, Vol.1004, p.175875, Article 175875
• Main Authors: Adigamova, M.V., Malyshev, I.V., Lukiyanchuk, I.V., Tkachenko, I.A., Vyaliy, I.E., Egorkin, V.S.
• Format: Article
• Language: English
• Subjects: Alumina matrix, Ferromagnetic properties; LCMO; Particles; Plasma electrolytic oxidation
• ISSN: 0925-8388
• DOI: 10.1016/j.jallcom.2024.175875

The possibility of forming the La0.5Ca0.5MnO3/Al2O3/Al composite by modifying the aluminum oxide matrix, previously formed by plasma electrolytic oxidation (PEO), with calcium lanthanum manganite powder was shown. The aluminum oxide matrix represented a regular system of parallel cylindrical pores with a predominant diameter d ∼ 250–300 nm. According to scanning electron microscopy images of the surface and cross-section of the composite, the use of rubbing followed by annealing at 400 °C made it possible to firmly fix La0.5Ca0.5MnO3 particles on the surface and in the depth of the porous PEO layer. After the “rubbing + annealing” operation, the orthorhombic modification of the La0.5Ca0.5MnO3 powder was retained with a slight change in the crystal lattice parameters. The surface of the resulting composite contained 1.8 at% Ca, 2.3 at% Mn and 1.5 at% La. The formed composite exhibited weak ferromagnetism at 300 K; lowering the temperature to 3 K led to pronounced ferromagnetic ordering with a Hc value of ∼-855/649 Oe. [Display omitted] •La0.5Ca0.5MnO3 powder was synthesized by solid-state method at 1300 ºC.•Microporous Al2O3 matrix was formed by “soft” PEO in tartrate-fluoride electrolyte.•Rubbing + annealing was used to fix the particles in the pores of the Al2O3 matrix.•La0.5Ca0.5MnO3/Al2O3/Al composite exhibits pronounced ferromagnetism at 3 K.