Influence of samarium and iron substitution on structural and electrical properties of barium zirconate titanate solid solutions

Abstract

Solid solutions of (x)SmFeO 3 -(1-x)Ba(Zr 0.05 Ti 0.95 )O 3 : x = 0, 0.21, 0.22 and 0.23 were synthesized by the solid-state reaction route. Le-Bail analysis of the X-ray diffraction data and Raman spectra revealed the presence of the tetragonal phase (P4mm space group 99). The remnant polarization (P r ) was~4.08 µC/cm 2 and 1.04 µC/cm 2 for x= 0 and x= 0.21, respectively, while lossy loops were observed for x≥ 0.22. Canting of the antiferromagnetic spins and ferromagnetic exchange mechanism was responsible for the ferromagnetic feature in the samples. An increase in remnant magnetization (M r ) was observed with increases in x. The Nyquist plots revealed the existence of grain and grain boundaries in the overall impedance. Separation of the normalized plots of impedance (Z˝) and modulus (M˝) spectra indicated localized motion of the charge carriers in the sample. The Maxwell-Wagner model fits very well in the lowfrequency region (10 5 Hz). The ac conductivity obeyed the Universal Jonscher's Power law. The variations in the exponent n suggest that the conduction mechanism conforms to the small polaron hopping mechanism.

Dielectric Properties in Transition Metal and Rare‐Earth‐Doped Multiferroic BaTiO3 Nanoparticles

“…The ionic radius of Er (1.03 Å) is much smaller compared with that of the host Ba 2+ ion (1.61 Å), which causes a strong compressive strain. Reduced lattice parameters in rare earth doped on the Ba site BTO ceramics are also observed experimentally . Therefore, we have to use the relations where the exchange interaction constants in the defect places are greater compared with the bulk ones, i.e., , .…”

“…Reduced lattice parameters in rare earth doped on the Ba site BTO ceramics are also observed experimentally. [57][58][59][60] Therefore, we have to use the relations where the exchange interaction constants in the defect places are greater compared with the bulk ones, i.e., J d > J b , J 0 d > J 0 b . This is contrary to the case of Fe-doped BTO NPs where we have a tensile strain.…”

Fabrication and Characterization of Graphene-Barium Titanate-Graphene Layered Capacitors by Spin Coating at Low Processing Temperatures

“…This suggested that discharging of the space charge took place to lessen the impact of barriers in grain boundaries at high frequencies. 35,38 The Z' value decreased as frequency rised because charge carriers had less time to drift. At low frequencies, space charge polarization at electrodes was also thought to had a role in the Z' value consistency.…”