Structural, Vibrational, and Magnetic Characterization of Orthoferrite LaFeO Ceramic Prepared by Reaction Flash Sintering.

LaFeO perovskite ceramics have been prepared via reaction flash technique using FeO and LaO as precursors. The obtained pellets have been investigated using several techniques. The formation of LaFeO has been clearly confirmed by X-ray diffraction. The scanning electron microscopy micrographs have shown the microporous character of the obtained pellets due to the low temperature and dwell time used in the synthesis process (10 min at 1173 K). The orthorhombic-rhombohedral phase transition has been observed at approximately 1273 K in differential thermal analysis measurements, which also allows us to determine the Néel temperature at 742 K. The fitted Mössbauer spectra exposed the presence of a single sextet ascribed to the Fe ions in the tetrahedral site. Finally, magnetic measurements at room temperature indicate the antiferromagnetic character of the sample.