Lead-Free BNT-BT0.08/CoFe2O4 Core-Shell Nanostructures with Potential Multifunctional Applications

Synergistic magnetoelectric enhancement in 0-3 particulate multiferroic composites: unveiling the exceptional interplay of Ba0.85Sm0.15TiO3 and Co0.85Sm0.15Fe2O4 phases for superior energy conversion

This study investigates the complex investigation of the 0-3 particulate multiferroic properties found in composite materials. The materials used in this study are (1 - x)Ba0.85Sm0.15TiO3 (SmBT)-xCo0.85Sm0.15Fe2O4 (SmCF), and the research utilizes a combination of the solid-state reaction method and mechanical milling techniques. A cubic spinel secondary phase was discovered in Co0.85Sm0.15Fe2O4, while a tetragonal structure was found in Ba0.85Sm0.15TiO3. The M-H loops clearly indicate the presence of exchange interactions between spins with varying orientations within the domains. As the proportion of SmCF in the composites increased, the saturation magnetization and magnetic moments became stronger, indicating a greater level of exchange interactions. Through a temperature-dependent analysis, an increase was observed in both the dielectric constant (εr) and dielectric loss (tan δ). Nevertheless, there was a decrease in εr above the Curie temperature. It is worth mentioning that there was a significant increase in the magnetoelectric coupling constant, suggesting a stronger interaction between magnetic and electric fields. This increased interaction leads to a more effective conversion of electrical energy into its magnetic equivalent, indicating a significant improvement in overall energy efficiency. The results of our study shed light on a promising direction for the development of advanced multifunctional materials, which could have significant implications for energy-efficient applications.

Dielectric Properties of Electrical Insulating Liquids for High Voltage Electric Devices in a Time-Varying Electric Field

The motivation to improve components in electric power equipment brings new proposals from world-renowned scientists to strengthen them in operation. An essential part of every electric power equipment is its insulation system, which must have the best possible parameters. The current problem with mineral oil replacement is investigating and testing other alternative electrical insulating liquids. In this paper, we present a comparison of mineral and hydrocarbon oil (liquefied gas) in terms of conductivity and relaxation mechanisms in the complex plane of the Cole-Cole diagram and dielectric losses. We perform the comparison using the method of dielectric relaxation spectroscopy in the frequency domain at different intensities of the time-varying electric field 0.5 kV/m, 5 kV/m, and 50 kV/m. With the increasing intensity of the time-varying electric field, there is a better approximation of the Debye behavior in all captured polarization processes of the investigated oils. By comparing the distribution of relaxation times, mineral oil shows closer characteristics to Debye relaxation. From the point of view of dielectric losses at the main frequency, hydrocarbon oil achieves better dielectric properties at all applied intensities of the time-varying electric field, which is very important for practical use.