Structural, microstructural and Mössbauer study of BiFeO3 synthesized at low temperature by a microwave-hydrothermal method

Studies of La- and Pr-driven reverse distortion of FeO6 octahedral structure, magnetic properties and hyperfine interaction of BiFeO3 powder

“…7a); this means that there are at least two kinds of hyperne structures in the crystal lattice of the BLPFO powders. Therefore, at least two sextets exist in the Mössbauer spectra of BLPFO powders, which is also in accordance with the results of the studies conducted by Prado-Gonjal et al 45 In addition, the area ratio of the sextet lines is an unsatised ratio of 3 : 2 : 1 : 1 : 2 : 3, and this also implies the asymmetry of the Mössbauer spectra of the samples. Fig.…”

Synthesis, microstructure and properties of BiFeO₃-based multiferroic materials: A review

“…improvement in crystallinity and purity of the obtained BiFeO 3 samples with respect to the traditional hydrothermal processes [92][93][94]. However, the specific conditions in which a pure BiFeO 3 phase is obtained are again contradictory among different works.…”

“…The presence of Fe 2+ ions in BiFeO 3 materials has been widely studied [47,93,95,[112][113][114][115] considering that it may have a key role in the electromagnetic properties. In this sense, although analyses on BiFeO 3 single crystals by X-ray photoemission spectroscopy (XPS) has just detected iron in the 3+ oxidation state [112], more recent studies through Mössbauer spectroscopy [93] point towards the presence of a small amount of Fe 2+ in low spin configuration in BiFeO 3 ceramic powders.…”

“…In this sense, although analyses on BiFeO 3 single crystals by X-ray photoemission spectroscopy (XPS) has just detected iron in the 3+ oxidation state [112], more recent studies through Mössbauer spectroscopy [93] point towards the presence of a small amount of Fe 2+ in low spin configuration in BiFeO 3 ceramic powders. Actually the fluctuations in the oxidation state of iron cations can be promoted by applying a gas flux (air, O 2 , N 2 or Ar) during the thermal treatment [47,95,115].…”

Structure and phase transition of BiFeO3 cubic micro-particles prepared by hydrothermal method

“…Thus, researchers have attempted to control the BiFeO 3 particle shape and size by using hydrothermal or microwave-hydrothermal method [11][12][13][16][17][18]. Pure BiFeO 3 with irregular particles [19], wafer-like particle shapes [20], nanowires [12,21], tubes [22,23], spheres, and cubes [16,24] was synthesized at different KOH concentrations.…”