Sr 1−x Ba x Co 1−x Fe x O 3−δ (BSCF) nanoparticles were successfully synthesized with three modified wet chemical techniques; composite mediated hydrothermal method (CMHM), without water and surfactants (WOWS) sol-gel and co-precipitation methods. The probable electrical conduction mechanism of synthesized BSCF was explored via complex impedance analysis. Various physicochemical characterization techniques were employed to study the dependence of structure, homogeneity, physical parameters and electrical properties of BSCF on synthesis procedures. X-ray Diffraction (XRD) confirmed the formation of cubic BSCF perovskite structure. Fourier Transform Infrared Spectroscopy (FTIR) spectra indicated the presence of the fingerprint region of perovskite (ABO 3−δ ) structure. Scanning Electron Microscopy (SEM) images revealed uniformly diffused, micro porous and agglomerated morphology. Differential Thermal Analysis (DTA) and Thermogravimetry (TGA) verified the formation of intermediate metal carbonates that were decomposed to the final product. Nyquist plots against frequency (20 Hz-3 MHz) revealed single semi-circular arcs. The arc showed significant grain boundary contribution to total electrical conduction behaviour of BSCF material synthesized by CMHM and co-precipitation methods. Modulus analysis showed the Debye type conductivity relaxation in CMHM synthesized material. The AC conductivity graphs followed Jonscher's power law. Temperature dependent (RT to 600°C; 10 kHz) impedances showed decreasing trend that was an indication of thermally activated conduction process. A Correlation was established among structural and electrical conduction properties. Hydrothermally synthesized BSCF samples exhibited minimum impedances and maximum AC conductivity, which makes them a potential candidate for cathode material in (IT-SOFCs) applications.

Ferrites materials with Spinel structure have been broadly studied in recent years because of numerous technological applications. Lanthanum substituted Co-ferrites nanoparticles (CoLa0.075Fe1.925O4) were synthesized via chemical co-precipitation method. X-ray Diffraction study revealed that prepared nanoparticales are single-phased spinel ferrites. Lattice constant, crystallite size, theoretical densities were estimated from XRD data. Electrical properties have been investigated with frequency ranging from 20Hz to 3MHz at room temperature. Dielectric constant and dielectric loss factor shows decreasing trend with increasing frequency. Ac conductivity exhibit increasing behavior with increasing frequency. The contribution of grains and intergrain boundaries in conduction process was estimated from impedance study. Nyquist plot shows dominant contribution of grain boundary resistance than the grain resistance in conduction mechanism.

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Bulk specimens of Bi2Ca2-xCexCoO6 (x = 0.00, 0.20) were prepared in pure phase form using co-precipitation method. The monoclinic structure of all samples is revealed via X-Ray Diffraction (XRD) analysis. The crystallite size, lattice constant, lattice strain, and volume of the unit cell were all determined using XRD analysis. On sintered at 750°C for 2 hours, the average crystallite size was 32-38nm. The precision analyzer was used to determine the loss tangent tan (δ), dielectric constant (ε'), AC conductivity (σac) in the 20Hz-3MHz range. The conduction process of electrical conductivity was also investigated utilizing the Jonscher Power Law.