Mossbauer Spectroscopy Studies of Fe-Doped BaTiO3 Ceramics

The Fe-doped BaTiO3 ceramics with various iron concentration were prepared by the conventional ceramic technology. Structure of the samples was studied by X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Hyperfine interactions were determined using the Mossbauer spectroscopy. As confirmed by structural investigations, the obtained materials are good quality ceramics, homogeneous and free of iron oxides and Fe dopant clustering. It was found that Fe ions are incorporated into the tetragonal lattice of barium titanate, which is accompanied by the formation of oxygen vacancies. Paramagnetic behavior of Fe-doped BaTiO3 was observed in the Mossbauer spectra at room temperature as a superposition of singlet and two doublets. These components originate from Fe3+ ions which substitute Ti4+ ions at octahedral sites inside of less or more distorted oxygen octahedrons and at pentahedral sites, i.e., inside octahedrons with no one oxygen ion.