(BaTiO₃)_1‐x + (Co_0.5Ni_0.5Nb_0.06Fe_1.94O₄)_x nanocomposites: Structure, morphology, magnetic and dielectric properties

Abstract

Two phase-based nanocomposites consisting of dielectric barium titanate (BaTiO 3 or BTO) and magnetic spinel ferrite Co 0.5 Ni 0.5 Nb 0.06 Fe 1.94 O 4 (CNNFO) have been synthesized through solid state route. Series of (BaTiO 3 ) 1x + (Co 0.5 Ni 0.5 Nb 0.06 Fe 1.94 O 4 ) x nanocomposites with x content of 0.00, 0.25, 0.50, 0.75, and 1.00 were considered.The structure has been examined via X-rays diffraction (XRD) and indicated the occurrence of both perovskite BTO and spinel CNNFO phases in various nanocomposites. A phase transition from tetragonal BTO structure to cubic structure occurs with inclusion of CNNFO phase. The average crystallites size of BTO phase decreases, whereas that for the CNNFO phase increases with increasing x in various nanocomposites. The morphological observations revealed that the porosity is highly reduced, and the connectivity between grains is enhanced with increasing x content. The optical properties have been investigated by UV−vis diffuse reflectance spectroscopy. The deduced band gap energy (E g ) value is found to reduce with increasing the content of spinel ferrite phase. The magnetic as well as the dielectric properties were also investigated. The analysis showed that CNNFO ferrite phase greatly affects the magnetic properties and dielectric response of BTO material. The obtained findings can be useful to enhance the performances of magneto-dielectric composite-based systems.

Microstructure and physical properties of Sr2CrHfO6 ferrimagnetic double‐perovskite oxides

“…Such phenomenon results from dipole and space charge polarization 41 . Similar results were reported for Eu‐substituted Bi–Fe–Mn perovskite oxides with the chemical formula Bi 1‐x Eu x (Fe 0.8 Mn 0.2 )O 3 ( x = 0.00–0.04), 42 and for nanocomposites composed of BaTiO 3 and magnetic spinel ferrite (Co 0.5 Ni 0.5 Nb 0.06 Fe 1.94 O 4 ) 43 . At low frequency, both dipolar and space charges in the ceramic samples can contribute to the high ε r value.…”

“…41 Similar results were reported for Eusubstituted Bi-Fe-Mn perovskite oxides with the chemical formula Bi 1-x Eu x (Fe 0.8 Mn 0.2 )O 3 (x = 0.00-0.04), 42 and for nanocomposites composed of BaTiO 3 and magnetic spinel ferrite (Co 0.5 Ni 0.5 Nb 0.06 Fe 1.94 O 4 ). 43 At low frequency, both dipolar and space charges in the ceramic samples can contribute to the ε r value. However, they are unable to follow the change in the frequency of applied electric field in the high frequency region, and a relaxed dielectric behavior appears, leading to a fast decrease in ε r .…”

Enhancement of microstructure characteristic and dielectric constant of BaMn0.05Ti0.95O3 ceramics

“…Further, based on Table 1, the higher sintering temperature enlarges the crystal size of the sample. Here, a higher sintering temperature induces more diffusion and agglomeration of atoms so that the crystal size becomes larger [24]. The results of the FTIR characterization area graph of the relationship between wavenumber (350-4000 nm -1 ) and transmittance are presented in Figure 2.…”

Co-relation between Rietveld analysis, dielectric studies and impedance spectroscopy of the Ba1−xSrxTiO3 ceramics

“…Advanced materials attract tremendous attention of researchers for further advancement in their versatile applicability [1][2][3][4]. Ferroic materials have been studied extensively since a long period due to its potential in a variety of applications of material science and technology [5][6][7][8][9][10][11]. Perovskite materials such as barium titanate (BT) are the frequently used for various applications such as capacitors, sensors, memory devices, actuators, infrared detectors, and optical, acoustic, and tunable microwave devices etc.…”