| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1617118 | Journal of Alloys and Compounds | 2011 | 6 Pages |
Polycrystalline Bi1−xBaxFe1−yMyO3 (M = Co and Mn; x = 0.1, y = 0.1) were synthesized by solid-state route method to study the compositional driven structural transformations in multiferroics. Room temperature X-ray diffraction patterns confirmed the formation of perovskite structure. Rietveld-refined crystal structure parameters revealed the existence of rhombohedral R3c symmetry for both the samples. The samples were found to be nearly free from any other secondary phases. Raman analysis reveals that Ba atom substitutes Bi site and Mn and Co atom substitutes Fe site into the BiFeO3 with the shifting of phonon modes. The red shift is attributed to Co or Mn doping where as blue shift occurs from Ba doping. The differential scanning calorimetry reveals the corresponding Neel temperature 370 °C and 326 °C for Co and Mn doped samples. Ba and Co substitution with x = 0.1 and y = 0.1 has not affected the Neel temperature of the parent BiFeO3 as well of Ba and Mn substitution. The variation of frequency dispersion in permittivity and loss pattern due to A-site and B-site substitution in BiFeO3 was observed in the dielectric response curve.
► XRD confirms single-phase rhombohedral structure with space group R3c. ► Raman spectra reveal shifting of active phonon modes due to doping. ► Reduction of TN in the Mn-doped BBFO sample as compare to Co-doped. ► At lower frequency the dipoles follow the frequency of the applied field. ► Larger ɛ′ and small tan δ is observed for Mn-doped sample at 1 MHz.
