Investigation of complex impedance and modulus properties of Nd doped 0.5BiFeO3-0.5PbTiO3 multiferroic Composites

Abstract0.5BiNdxFe1−xO3 − 0.5PbTiO3 (BNxF1−x − PT)(x = 0.05, 0.10, 0.15, 0.20) composites were successfully synthesized by a solid state reaction technique. At room temperature, X-ray diffraction shows tetragonal structure for all concentrations of Nd doped 0.5BiFeO3 − 0.5PbTiO3 composites. The nature of Nyquist plot confirms the presence of bulk effects only for BNxF1−x − PT (x = 0.05, 0.10, 0.15, 0.20) composites. The bulk resistance is found to decreases with the increasing temperature as well as Nd concentration and exhibits a typical negative temperature coefficient of resistance (NTCR) behavior. Both the complex impedance and modulus studies have suggested the presence of non-Debye type of relaxation in the composites. Conductivity spectra reveal the presence of hopping mechanism in the electrical transport process of the composites. The activation energy calculated from impedance plot of the composite decreases with increasing Ndx concentration and found to be 0.89, 0.76, 0.71 and 0.70 eV for x=0.05, 0.10, 0.15 and 0.20 respectively.