Structural, magnetic and electrical properties of BiFeO3 co-substituted with Pr–Mn

• XRD patterns indicates a contraction of unit cell due to substitution.
• Charge states of Bi, Pr, Fe and Mn are found to be +3.
• No significant change in morphology is observed for the co-substituted samples.
• Weak induced ferromagnetic property at low fields for co-substituted samples.
• Resistivity of the x = 0.20 shows a stable behaviour when compared to other samples.

Samples of stoichiometry Bi1 − xPrxFe1 − xMnxO3 (x = 0, 0.10, 0.15, 0.20) have been synthesized by solid-state reaction method. Fe is found to be in the mixed and single oxidation states for pure and substituted samples, respectively. Mn is in +3 state, as inferred from XPS. XRD analysis indicates the formation of stoichiometric phase with control over the Bi and Fe rich secondary phases. The x = 0.10 sample shows thermal stability and characteristic ferroelectric–paraelectric transitions are observed in all the samples, from the thermal studies. Effect of substitution on the grain size distribution is not observed in the SEM picture. Magnetization values from the hysteresis curves obtained at the maximum applied field, increases with substitution indicating the effect of Pr–Mn in BiFeO3. The substituted samples show different response in resistivity and dielectric behaviour than the pure sample, as understood from impedance spectroscopy data. Defects, and charge carriers resulting from Pr–Mn substitution are responsible for this change in conductivity.

Figure optionsDownload as PowerPoint slide