Synthesis of type-II based (1-x)Ba0.6(Ca1/2Sr1/2)0.4Ti0.5Fe0.5O3+(x)Ni0.40 Zn0.45Cu0.15Fe1.9Eu0.1O4 composites via standard solid state reaction method and investigation of multiferroic properties

Abstract

A series of multiferroic composites, (1-x)Ba0.6(Ca1/2Sr1/2)0.4Ti0.5Fe0.5O3+(x)Ni0.4Zn0.45 Cu0.15Fe1.9Eu0.1O4 ((1-x)BCSTFO+(x)NZCFEO) where x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 1.0 have been synthesized by standard double sintering ceramic method sintered for 3 hours at 1200°C in air. The X-ray diffraction patterns reveal that the multiferroics and the parent ceramic samples crystallize in simple cubic structure with a slightly distored lattice parameter. The X-ray and bulk density increase with the increasing ferrite content. Consequently, the porosity decreases indicating better crystallization. A decreasing trend in dielectric constant is observed while the relative quality factor (RQF) increases significantly with the increasing ferromagnetic NZCFEO. At the same time, M–H hysteresis loops reveal that ferromagnetic property enhances with the addition of Ni0.40Zn0.45Cu0.15Fe1.9Eu0.1O4 (NZCFEO). The highest values of coercive field ∼ 92 O and saturation magnetization ∼1.37 emu/g are observed for x = 10% and x = 50% compositions respectively. Additionally, the permeability enhances up-to x = 30% but decreases with further doping. The room temperature resistivity rises due to the decrease in hopping mechanism. The samples exhibit a decreasing trend for resistivity with the increase of temperature. The dopant concentration has also shown an impressive impact on the activation energy. As a result, the multiferroic properties of (1-x)BCSTFO+(x)NZCFEO have been significantly improved considering the measured magnetic and ferroelectric properties.

Giant effect on structural, magnetic, electrical, and optical properties of lead-free Ba0.6Sr0.4Ti1-xAlxO3 ceramics via Sr and Al Co-doping engineering

“…Figure 11 shows the change of the real component (ε′) of complex dielectric constant (ε * =ε′ − jε′′) for different Ba 0.6 Sr 0.4 Al 1-x Ti x O 3 (where x=0.00, 0.05, 0.01, 0.15, 0.20) ceramics with a wider frequency range (5 kHz-5 MHz) at standard room temperature. This decreased frequency dispersion of ε′ is the characteristic of ferroelectric and dielectric materials and may be explained by interfacial polarization postulated by Maxwell-Wagner [89][90][91], which agrees with Koop's phenomenological hypothesis [84]. The compositional inhomogeneities produce interfacial defects, grain structure, impurities, and porosity, contributing to interfacial polarization.…”

“…This effect causes an impediment to spin and domain wall motion. As a result, permeability drops dramatically, and loss rises [84]. Notably, the oxygen vacancy concentration, which serves as a mechanical obstruction against the domain wall, may affect the domain wall's motion [85].…”

Impact of V substitution on the physical properties of Ni–Zn–Co ferrites: structural, magnetic, dielectric and electrical properties

“…Consequently, the decrease of grain size also revealed the reduction of the conductive area. [77] Hence, the electrical resistivity is expected to be increased owing to V substitutions as shown in…”