Structural transformation and multiferroic properties of Ba–Mn co-doped BiFeO3

• Pure and Ba–Mn co-doped BiFeO3 were synthesized by mechano-synthesis technique.
• A structural transition from rhombohedral (R3c:H) to the biphasic structure (R3c:H + P4mm) is obtained for 20% co-doping.
• The co-doping of Ba–Mn was found to be useful to enrich magnetic and ferroelectric properties simultaneously.
• The ME voltage coefficient measurements further proves the multiferroic nature of the pure and co-doped BFO.

Pure BiFeO3 and Bi1−xBaxFe1−xMnxO3Bi1−xBaxFe1−xMnxO3 (x=0.10,0.20x=0.10,0.20) fine ceramics were synthesized using mechano-synthesis route. The influence of co-doping (Ba–Mn) on structural and multiferroic properties of BiFeO3 has been studied in different experimental conditions. X-ray diffraction patterns, Rietveld structural refinement of XRD patterns and Fourier transform infrared (FTIR) spectra reveal the structural transition from rhombohedral (R3c) to the biphasic structure (R3c + P4mm) on co-doping. The co-doping improves surface morphology and also reduces the particle size. The room temperature M–H loops of all samples showed antiferromagnetic/weak ferromagnetic behavior. Magnetoelectric coupling coefficient determination is carried out to reveal extent of intimate interaction between electric and magnetic dipoles interaction in the samples. Room temperature occurrence of ferromagnetism, ferroelectricity and magnetoelectric effect supports the observation of multiferroism and magnetoelectric coupling in BiFeO3. Thus, co-doping at Bi- and Fe-sites of BiFeO3 can improve multiferroic properties of BiFeO3 for various applications.