Barium titanate (BaTiO 3 ) thin films have been prepared using the spray pyrolysis method. The films were deposited onto a glass substrate at varying substrate temperature ranging from 250 to 350°C with the interval of 50°C. The structural, morphological, electrical and dielectric properties of the deposited films have been studied. The X-ray diffraction pattern confirmed the polycrystalline nature of the films with a cubic crystal structure. X-ray photoelectron spectroscopy (XPS) showed a good agreement of the thin films stoichiometry with BaTiO 3 . A presence of Ba, Ti and O in the BaTiO 3 thin films was observed by energy dispersive X-ray analysis. The scanning electron microscopy (SEM) showed the heterogeneous distribution of cubical grains all over the substrate. The grain size decreased with an increase in substrate temperature. The dielectric constant and dielectric loss showed the dispersion behaviour as a function of frequency, measured in the frequency range of 20 Hz to 1 MHz. The AC conductivity (σ ac ) measurement showed the linear nature of obtained films, which confirms conduction mechanism due to small polarons. Impedance spectroscopy has been used to study the electrical behaviour of BaTiO 3 ferroelectric thin films. The ferroelectric hysteresis loop has been recorded at room temperature.

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In the present paper, study the acoustical properties of lead oxide nanoparticles through the measurement of ultrasonic velocity and density of lead oxide nanoparticles as a ligand in 70% dioxane + water, 70% methanol + water, and 70% ethanol + water mixtures‐based solutions has been carried out, this measurement is important for understanding the particle–particle, particle–solvent, and molecular interaction. The reported nanoparticles of lead oxide by using biological method such as using plant extract, but their acoustical properties of lead oxide nanoparticles are attracted the attentions of many researchers. Hence, the present investigation is focused on the study of acoustical parameters of lead oxide nanoparticles like adiabatic compressibility (β), acoustic impedance (Z), free length, and relative association by using the nanofluid interferometer. These measurements are carried out at frequency 2 MHz and temperature 305 K (at room temperature). The obtained results are helped to observe the behavior of ultrasonic velocity and acoustic properties at different concentrations range of ligand (i.e., lead oxide nanoparticle) such as 0.01, 0.05, 0.10, and 0.15 mol dm−3 reveal the presence of interaction between particle–particle, particle and solvent.

Co0.7-xNixMn0.3Fe2O4 (CNMFO) ferrites with x = 0.00, 0.05, 0.10 and 0.15,PbZr0.52Ti0.48O3(PZT) ferroelectric and 30% CNMFO – 70% PZT magneto electric(ME) composites were synthesized by double sintering ceramic method. XRD confirms pure phase formation for all compositions of ferrite, ferroelectric and ME composites. All compositions of ferrites, ferroelectric and ME composites show negative temperature coefficient of resistance (NTCR) confirming the semiconducting behavior, though the conduction mechanism is quite different than known semiconductors such as, silicon and germanium. The conduction, due to electron hoping in semiconductors against polaron hoping in ferrites is explained. The effect of cation distribution on resistivity of ferrite phase is also discussed. Thus, effect of polaron hoping and cation distribution on resistivity and dielectric constant of ferroelectric and ME composites has been discussed. Effective resistance of ME composites due to combined resistance of the constituent phases has also been studied.