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Synthesis of polycrystalline (Pb1-xNdx)(Ti1-xFex)O3(for x = 0.21–0.30) solid solutions using solid-state reaction method has been reported. The structural, dielectric, ferroelectric, magnetic, and magnetoelectric properties of the resulting solid solutions have been investigated in detail. The XRD data show that the phase transition occurs at 0.27 ≤ x ≤ 0.28 at room temperature. The dielectric studies show that the transition temperature continuously decreases with increasing "x". So it is clearly evident from XRD and dielectric data that the tetragonal to cubic phase transition occurs at x = 0.27 to x = 0.28 at room temperature. The remnant polarization (Pr) decreases from 19.78 μC/cm2 to 11.13 µC/cm2 gradually up to x = 0.25 whereas other samples exhibit lossy behavior. The remnant magnetization (Mr) continuously increases from 0.068 emu/g to 0.467 emu/g with composition. All samples exhibit a positive magnetoelectric effect which is the strongest in x = 0.22 sample. [ABSTRACT FROM AUTHOR]

The perovskite ( La 0. 7 Ba 0. 3) ( Mn 0. 5 Fe 0. 5 ) 1 − x Zr x O3, where x = 0.1, 0.2 and 0.3, ceramics were synthesized by solid-state reaction method. The introductory structural studies were followed through by X-ray diffraction technique and the results have disclosed that all the samples were crystallized into an isolated phase. The Zr substitution in the resulting solid solutions increases the electrical conductivity and the maximum value of ac conductivity has been found to be ∼ 118.8 S . cm − 1 for x = 0.3 at 200 ∘ C (at 1 MHz). The frequency dependence of ac conductivity data follows Jonscher's power law. The variation of the exponent n versus temperature follows the nonoverlapping small polaron tunneling (NSPT) model. The dielectric relaxation has been observed to be of non-Debye nature for all measuring temperatures (50–200 ∘ C). The impedance spectroscopy reveals that all the samples exhibit negative temperature coefficient of resistance (NTCR) behavior. The prepared samples (for x > 1) are supposed to be suitable for cathode materials in SOFCs. [ABSTRACT FROM AUTHOR]

Nd1−xPbxFeO3 (x = 0.1–0.3) solid solutions were prepared by aliovalent substitution of Pb2+ at the Nd3+ site using the conventional solid-state reaction route. The structural, magnetic and dielectric properties and hopping mechanism of these solid solutions are reported. XRD data shows that all the samples possessed orthorhombic crystal structures. No impurity phase was found, indicating that Pb2+ was well within its solid solubility limit. All samples exhibited magnetic ordering with the Mr value decreasing from 2.42 emu/g for the x = 0.1 sample to 1.79 emu/g for the x = 0.3 sample. The coexistence of the multi-valance state of the Fe ion was explored using XPS analysis. The dielectric constant (ε׳) and dielectric loss (ε״) were found to decrease with increases in the frequency of the applied electric field and to show Cole–Cole relaxation behavior. The temperature-dependent variation of exponent "n" (obtained from the Jonscher's power law fitting) explains the conduction model that the system follows exactly. [ABSTRACT FROM AUTHOR]