Effect of Mn doping on crystal structure, dielectric and magnetic ordering of Bi0.8Ba0.2FeO3 multiferroic

Bi0.8Ba0.2Fe1-xMnxO3 (x=0.0, 0.1, and 0.2) multiferroics were synthesized by the conventional solid state reaction method. Structural characterization was performed using powder X-ray diffraction at room temperature which shows that all samples possess a rhombohedrally distorted perovskite structure described by the space group R3c. Rietveld refinement confirmed a good agreement between the observed and calculated patterns. Magnetic measurements were carried out at room temperature up to a field of 15 kOe. Ba and Mn co-substitution transformed antiferromagnetic BFO into ferromagnetic. This transformation is related to partial modification in the structure. Dielectric response of all synthesized samples was analyzed in the frequency range 10 Hz to 5 MHz at different temperatures by impedance/gain phase analyzer. The value of dielectric constant and dielectric loss show dispersion at low frequency for various temperatures in all the samples. For 10% substitution of Mn, epsilon increases and tan delta decreases significantly. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.