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The spark-plasma sintering of ceramics based on the cubic pyrochlore phase in the system Bi2O3-ZnO-Nb2O5 is reported for the first time. It is shown that the use of spark-plasma sintering in the manufacture of (Bi1.5Zn0.5)2(Zn0.5Nb1.5)2O7 ceramics makes it possible to obtain a high density, a homogeneous microstructure, and high dielectric parameters (almost 30% higher compared to conventional ceramic technology). The paper discusses the features of microstructure formation and the optimization of spark plasma sintering regimes. [ABSTRACT FROM AUTHOR]

The present work centered attention on novel ionic liquid (IL) based on dicationic benzimidazolium ion containing amide group (DBimIL) synthesized using dialkylation of N-ethyl benzimidazole to followed with anion exchange reaction. To explore the potential application of ILs, there is a great need to grasp their structural and physical properties. We have developed three different set of DBimIL based ionic liquids with chloride, hexafluorophosphate and perchlorate anions in aqueous media, respectively. Their structural features were studied using 1H, 13C-NMR, FTIR, and HRMS spectroscopy, respectively. The temperature-dependent dielectric characteristics of ILs were closely examined angular frequency in the range of 0.6–125 rad/s from 30 to 150 °C. The relationship between the structural and dielectric properties of ILs established. The dielectric parameters like dielectric constant, dissipation factor and the real part of ac conductivity were found to be affected significantly with the tuning of anionic moieties of ionic liquids. The ability of materials to store a charge in electromagnetic field was measured. From dielectric and electrical studies, to bring to an end, especially in particular way that the present IL systems have an enormous potential for the designing of modern-day energy storage devices. [ABSTRACT FROM AUTHOR]

The CaSn0.95Mn0.05O3 (CSMO) was produced by using the sol-gel wet chemical process. The structural composition was examined using an X-ray diffraction (XRD) pattern, and the presence of an orthorhombic structure with the space group Pbnm was confirmed by Rietveld refinement. At different temperatures between 300 K and 773 K, the dielectric permittivity (ε), tangent losses (tanδ), and electrical conductivity of CSMO has been measured as a function of frequency from 100 Hz to 1 MHz.Dielectric permittivity (ε) is found to be independent of temperature up to 400K and very low tangent loss. Jonscher's power law in the material's frequency-dependent ac conductivity shows its semiconductor nature. Optical band gap of CSMO was observed by using UV-vis.absorption spectra. The optical band gap of CSMO, which was determined using Tauc plot measurements to be 2.42 eV, suggests that the sample is a semiconductor. The Arrhenius model is employed to perform an analysis of the dc conductivity of the material concerning both frequency and temperature. As a result of its semiconductivity, stable dielectric constant, and low tangent loss, CSMO is a suitable material for thermally stable capacitors, semiconductor devices, UV filter and UV detectors. [ABSTRACT FROM AUTHOR]

Sol-gel method is used to synthesize the Bi0.90Dy0.10FeO3-BaTi0.95Hf0.05O3 (BDyFO-BTHfO composite) multiferroic composite material. The structural formation was examined utilizing an X-ray diffraction (XRD) pattern preceded by Rietveld refinement utilizing the FULLPROF programme to confirm the presence of tetragonal and partially rhombohedral structures having space group P4mm and R3c, respectively. The dielectric characteristics of the BDyFO-BTHfO composite have been measured with respect to frequency (100 Hz to 1 MHz) and temperature (RT to 663K). Dielectric permittivity (ε) shows low-frequency dispersion which can be addressed by Maxwell-Wanger-type interfacial polarization. The synthesized composite material exhibits a negative magneto-dielectric (MD) effect when a magnetic field is operated (0.0 T to 2.0 T) and the obtained values are −9.61% and −19.68% for the ε and tanδ, respectively, at 1 kHz. The contribution of the grains, grain boundaries and electrode effects on the resistive characteristics of the samples was evaluated using comprehensive impedance spectroscopy using a Nyquist plot. The band gap (Eg) absorption of the synthesized sample was determined using Tauc's formula and found to be 2.05 eV. The BDyFO-BTHfO composite has improved magneto-dielectric, magneto impedance, and optical properties that support their potential usage in microelectronics, energy storage devices, and optoelectronic devices. [ABSTRACT FROM AUTHOR]

A polycrystalline ceramic oxide, BaFe2MnO6 was produced through a regular solid-state route. The phase creation in the synthesized substance was investigated through X-ray diffraction (XRD) technique. The present material has found with made up of a single phase orthorhombic structure. The electrical properties of the compound were recorded through an LCR meter for a broader range of frequencies and temperatures. This perovskite oxide material possesses a large relative permittivity (ɛr = 1139) and low dielectric loss (tanδ = 0.421) at the ambient atmospheric condition, while the curie temperature arise beyond 450 °C. The resultant dielectric properties of this material assure its promising candidature for feasible applications in smart electronic devices such as dielectric material in ceramic capacitors. [ABSTRACT FROM AUTHOR]

In this article, the synthesis (through a mixed oxide route, calcination temperature = 850 °C, sintering temperature = 870 °C, for time= 6 h) and characterization (structure, dielectric, and electrical properties) of Gd modified bismuth titanate Bi4Ti3O12 of a chemical composition Bi3.8Gd0.2Ti3O12 of Aurivillius family in ceramic form have been reported. The development of an orthorhombic structure (with a minor secondary phase) with a space group B2ab has been confirmed by analyzing room temperature X-rays diffraction pattern/data. Studies of some electrical parameters like loss tangent, dielectric constant, electric impedance, and conductivity have provided valuable data and information on conduction mechanism, structure-properties relationship, etc., in the 25–500° C temperature range at different frequencies (1 kHz − 1MHz). The presence of grain, grain boundary is confirmed from the Nyquist plot. The Nyquist plot also confirms the existence of non-Debye relaxation in the material. The frequency and temperature significantly impact the material's various properties (dielectric and electrical). [ABSTRACT FROM AUTHOR]

There are many nanoparticle preparation techniques such as the biological approach sol-gel method and physical methods, etc. However, the co-precipitation approach requires few chemical reagents and reaction time as well as produces highly pure products with comparatively lower costs among the available techniques. In present work co-precipitation method is use to synthesize magnetic iron oxide (Fe3O4) nanoparticles, followed by characterization to check its applicability and the presence of undesired substrate. UV–visible spectroscopy, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and Fourier-Transform Infrared Spectroscopy (FTIR) were examined to determine the synthesized Fe3O4 nanoparticles. The nanoparticles' sizes lies between 1 nm to 100 nm, according to the SEM and HR-TEM analyses. XRD measurements verified the crystalline characteristics of the Fe3O4 nanoparticles. Dielectric spectroscopy of synthesized Fe3O4 nanoparticle pellets has been investigated at a wide frequency range 0.1 to 105 Hz. Capacitance and dielectric permittivity of Fe3O4 nanoparticles decrease continuously with frequency as dipole gets less time to orient in the field. The dielectric permittivity of Fe3O4 pellets increases up to 3 mm thickness and subsequently drops, perhaps because a rise in resistance. The electrical conductivity of Fe3O4 rises exponentially with frequency. According to the dielectric studies, the dielectric permittivity and electrical conductivity of Fe3O4 are greatly dependent on the thickness and extent of frequency. Additionally, the dielectric impedance of Fe3O4 pellets has also been investigated as a function of frequency. [ABSTRACT FROM AUTHOR]