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In this study, solid solutions of (1-x)BaTiO3-xBiMnO3 have been synthesized by an aqueous sol-gel method. It was determined that single-phase compounds can be obtained up to x = 0.6 and with further increase in percentage of BiMnO3 component additional crystal phases were detected. Perovskite crystal structure was determined for all synthesized compounds regardless of chemical composition. Raman spectra of synthesized solid solutions showed gradual change of the shape with an increase of BiMnO3 fraction. It was demonstrated that partial substitution of BaTiO3 by BiMnO3 led to the drastic growth of grains of the end products. Magnetization measurements showed that all BiMnO3-containing samples are characterized by paramagnetic behavior. Clear correlation between magnetization values and composition of the materials was observed, magnetization values increased with increasing of BiMnO3 content in solid solutions.

In this study, the BixLa1−xMnO3+δsolid solutions (xfrom 0 to 0.65) were synthesized using sol–gel combustion method with citric acid as a fuel and complexing agent. It was shown that changes in chemical composition of the materials lead to the evolution of crystal structure, morphology, and magnetic properties. The thermal behavior of precursor gel was investigated by thermogravimetric and differential scanning calorimetry (TG-DSC) measurements. X-ray diffraction (XRD) analysis demonstrated that all samples were monophasic. The Rietveld analysis showed that the structure can be indexed by trigonal or cubic unit cell depending on Bi3+content. Scanning electron microscopy (SEM) was used to evaluate morphological features of the synthesized materials and revealed that Bi3+ions significantly promote growth of the grains. The sol–gel-derived BixLa1−xMnO3+δspecimens were also characterized by FT-IR spectroscopy and magnetization measurements, which showed a clear correlation between magnetic properties and crystal structure of the materials.

In this study, the aqueous sol-gel method was employed for the synthesis of (1&minus, x)SrTiO3-xBiMnO3 solid solutions. Powder X-ray diffraction analysis confirmed the formation of single-phase perovskites with a cubic structure up to x = 0.3. A further increase of the BiMnO3 content led to the formation of a negligible amount of neighboring Mn3O4 impurity, along with the major perovskite phase. Infrared (FT-IR) analysis of the synthesized specimens showed gradual spectral change associated with the superposition effect of Mn-O and Ti-O bond lengths. By introducing BiMnO3 into the SrTiO3 crystal structure, the size of the grains increased drastically, which was confirmed by means of scanning electron microscopy. Magnetization studies revealed that all solid solutions containing the BiMnO3 component can be characterized as paramagnetic materials. It was observed that magnetization values clearly correlate with the chemical composition of powders, and the gradual increase of the BiMnO3 content resulted in noticeably higher magnetization values.

In the present work, a series of powdered Y1-xGdxFeO3 solid solutions (x from 0 to 1) was prepared by an aqueous sol-gel method. Structural properties of the synthesized species were investigated using powder X-ray diffraction (XRD), Raman and Mossbauer spectroscopies. It was demonstrated that single-phase compounds can be obtained in the whole compositional range between the end members of the series. Raman study revealed a gradual change of the Raman spectra depending on the chemical composition of samples. Room-temperature magnetic properties were shown to be strongly dependent on the ratio of Y3+ and Gd3+ ions in analyzed species. Consistent transition from hysteresis characteristic of YFeO3 to almost linear dependence of magnetization of GdFeO3 was observed with an increase of Gd content in prepared powders. On the other hand, this transition was accompanied by a significant increase of magnetization values.

In this study, BiFe1-xMnxO3 (BiFeMnO; x from 0 to 0.5) solid solutions were prepared by low temperature sol-gel processing. It was demonstrated that structural, magnetic and morphological properties of BiFeMnO samples are dependent on the chemical composition of the synthesized BiFe1-xMnxO3 solid solutions. The thermal behaviour of the Bi–Fe–Mn–O precursor gels was investigated by thermogravimetric and differential scanning calorimetry (TG-DSC) measurements. From X-ray diffraction (XRD) analysis it was observed that monophasic BiFe1-xMnxO3 samples have formed up to 25 mol% of substitution. The Rietveld analysis showed that the structure of BiFeMnO specimens can be indexed by rhombohedral or orthorhombic unit cell depending on Mn3+ content. Scanning electron microscopy (SEM) was used to investigate samples morphology and revealed, that smaller particles form when Mn3+ is present inside the structure. Moreover, magnetic properties of solid solutions were also investigated, and antiferromagnetism and weak ferromagnetism were observed for the samples.

In this study, a highly crystalline bismuth ferrite (BFO) powder was synthesized using a novel, very simple, and cost-effective synthetic approach. It was demonstrated that the optimal annealing temperature for the preparation of highly-pure BFO is 650 &deg, C. At lower or higher temperatures, the formation of neighboring crystal phases was observed. The thermal behavior of BFO precursor gel was investigated by thermogravimetric and differential scanning calorimetry (TG-DSC) measurements. X-ray diffraction (XRD) analysis and M&ouml, ssbauer spectroscopy were employed for the investigation of structural properties. Scanning electron microscopy (SEM) was used to evaluate morphological features of the synthesized materials. The obtained powders were also characterized by magnetization measurements, which showed antiferromagnetic behavior of BFO powders.