In this work, we report synthesis and characterization of the new La2SrCo2FeO9 triple perovskite material. The samples were produced by the solid state reaction method from high purity precursor powders of La2O3, SrCO3, Co2O3 and Fe3O4. The analysis of XRD patterns were made by Rietveld refinement through the GSAS code. The results reveal the presence of peaks, which are characteristics of the complex perovskite systems, and showed that La2SrCo2FeO9 crystallizes in an orthorhombic structure, space group Immm (#71). The lattice parameters were a=5.4314(3) ˚ A, b=5.4583(3) ˚ A and c=7.7018(2) ˚ A. The surface morphology was studied by scanning electron microscopy (SEM) and composition was analyzed using energy dispersive spectrometry (EDX). The SEM micrographs evidence a strongly diffused granular morphology with mean grain size of 2 „m and the EDX spectra show that the chemical composition of samples are in good agreement with the nominal values of the stoichiometric formula. Measurements of magnetization as a function of temperature permitted to determine the ferromagnetic characteristic of material with an effective magnetic moment of 9.7 „B, which are in agreement with the value calculated from the Hund’s rule.
Tópico:
Magnetic and transport properties of perovskites and related materials