Microstructural and optical property study of Samarium ferrite (SmFeO₃) powder via hydrothermal microwave

Full text: Perovskite oxides with the basic formula ABO₃ have been considered attractive among the oxide mixtures when used in catalytic environment-friendly systems [1]. Samarium ferrite (SmFeO₃) is one of these promising members of rare earth perovskite type oxides and has been used as a gas sensitive material, cathode in solid oxide fuel cells, magnetic compound and catalyst [2]. The structure of SmFeO₃ can be described as a three-dimensional network of FeO₆ octahedra surrounding the Sm atoms, where the Fe-O-Fe angle moves away from 180 °. This angle depends directly on the size of the rare earth: the larger the rare earth used, the more octahedra strands extend, and the Fe-O-Fe bond angle approaches 180°, and the lattice tends to be cubic. This angle directly directs the distance between the 2p oxygen orbitals and the 3d iron orbitals, which are mainly responsible for the electrical and optical properties. The distortion makes the system interesting to understand the relationship between structure and properties. Its crystallization occurs in the distorted perovskite structure (orthorhombic space group: Pnma) [3]. For this study Samarium ferrite (SmFeO₃) microcrystals were prepared by the co-precipitation method and processed via a hydrothermal microwave. The structural characterization of this material obtained by co-precipitation and after processing will be performed by X-ray diffraction, Raman spectroscopy. Their morphology was investigated by field emission gun scanning electron microscopy (FEG-SEM) and the optical properties were analyzed by photoluminescence (PL). Keywords: Hydrothermal microwave synthesis, Photoluminescence, Samarium ferrite. References: [1] M. Mori et al.;Catalysis Today, 139, (2008), 125–129. [2] Z. Behzadifard et al.;Journal of Molecular Liquids, 262, (2018), 533–548. [3] E. Haye et al.;Journal of Alloys and Compounds, 657, (2016), 631-638. (author)