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Polymer-based energy storage materials are widely utilized in the fields of electrical and electronics due to their high-power density and excellent charge-discharge efficiency. In this study, polyetherimide (PEI) composite films with outstanding energy storage properties were prepared by growing an inorganic barrier layer of boron nitride (BN) on the surface of PEI films through the in situ chemical vapor deposition (PECVD) method. The effects of BN deposition time on the dielectric properties, leakage current density, and energy storage properties of the composite films were investigated. The results reveal that the BN inorganic barrier layer, prepared by the PECVD method, demonstrates excellent interfacial compatibility with the PEI polymer matrix and forms a densely deposited layer. The BN inorganic barrier layer effectively suppresses carrier injection at the electrode, reduces the current density inside the PEI composite film, and improves the breakdown strength of the composite film. The composite film exhibits optimal performance when BN is deposited for 20 min. At an electric field strength of 660 MV/m, the energy storage density of the composite film reaches 6.08 J/cm3, which is 1.53 J/cm3 higher than that of pure PEI, while maintaining a charge-discharge efficiency of 90.43%. The findings of this study provide valuable theoretical support for the design of polymer-based energy storage materials. [ABSTRACT FROM AUTHOR]

One of the negative effects of ferroelectric applications, particularly for electrocaloric effect (ECE) applications, is temperature hysteresis (ΔTHyst). Temperature hysteresis is the difference between the temperatures corresponding to the maximum dielectric permittivity in heating and cooling modes. The value of ΔTHyst is commensurate with the value of the ECE temperature change. The ECE is a phenomenon in which a material shows a reversible temperature change under an applied electric field. The aim of this work is to study the possibilities of temperature hysteresis reduction by varying the ceramic sintering temperature, changing the stoichiometry of BaxSr1-xTiO3 solid solutions, and changing the rate of the heating-cooling cycle. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of La2MoO6 ceramics were investigated in preparation for their application in mobile communication. La2MoO6 ceramics were prepared by the conventional solid-state method under varied sintering conditions. The X-ray diffraction peaks of La2MoO6 ceramic did not vary significantly with sintering conditions. The average grain size of La2MoO6 ceramics increased with increasing the sintering temperature and duration. The maximum density of 5.67 g/cm3, the dielectric constant ( ε r ) of 14.1, the quality factor (Q × f) of 68,000 GHz, and the temperature coefficient of resonant frequency ( τ f ) of −56 ppm/°C had been attained when La2MoO6 ceramics that sintered at 1300 °C for 4h. [ABSTRACT FROM AUTHOR]

The performance of the 0–3 piezoelectric composite consisting of two piezoelectric materials (PZT5H and PVDF) is analyzed to improve the piezoelectric properties for sensing applications using FEA and validated with the experimental and analytical results. The experimental and predicted results are showing good matches. The average piezoelectric coefficient d33 of the piezoelectric composite and the effective elastic, dielectric and piezoelectric properties of the 0–3 passive matrix piezoelectric composite were determined from the unit cell model. It is observed from the analysis that the performance of 0–3 piezo-composite has excellent piezoelectric properties and also optimized unit cell size and polymer matrix. [ABSTRACT FROM AUTHOR]

BiFeO3 nano-ceramics were synthesized using the low-temperature molten salt synthesis route to study the influence of calcination temperature and salt ratios. The Rietveld refinement revealed the distorted perovskite structure of BFO. These granular-shaped BFO samples' grains morphology was studied using the FESEM. The FTIR revealed the presence of Metal-Oxygen bonds in the BFO ceramics. The XPS studies exhibited the respective constituent elements' oxidation states and validated the presence of oxygen ion vacancies. The frequency-dependent dielectric properties were measured at various temperatures. The electrical conductivity measurement showed a linear variation as a function of frequency which validated Jonscher's power law. [ABSTRACT FROM AUTHOR]

This study investigates the dielectric properties, including dielectric constant (ɛ′), dielectric loss (ɛ″), tangent delta (tan δ), and AC conductivity (σac), of PVA/Y2O3 polymer nanocomposites (PNCs). The dielectric behavior of the PNCs was examined as a function of frequency and temperature. The results revealed that the addition of Y2O3 nanoparticles to the PVA matrix influenced the dielectric properties of the composites. In contrast to pure PVA, the PVA/Y2O3 PNCs with a 15 wt% Y2O3 loading exhibited high values of ɛ′, ɛ″, tan δ and σac are 647.49, 1607.48, 9.70 and 1.024 × 10−5, respectively, at low frequency and at particular temperature. Furthermore, the electrical properties of PVA/Y2O3 PNCs were also investigated using the Cole-Cole plots. These plots provide valuable insights into the complex impedance behavior and allow for comprehensive understanding of the electrical response of the nanocomposites. [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]

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 report, we are presenting the effect of B-site co-doping with Sn and Zr (2% each) on frequency and temperature-dependent dielectric and electrical properties of Ba0.5Sr0.5TiO3 (BST). The desired compound is synthesised following solid-state reaction route and the structural and micro-structural study of the resulting compound is done using X-ray diffractometer (XRD) and scanning electron microscope (SEM) technique. XRD study revealed that the parent structure of BST is mostly retained after co-doping. SEM micrograph analysis presented dense packing of grains of different sizes distributed all over the volume of compound formed. The compound was found to have a moderate value of dielectric constant and low tangent loss along with a near stable response of these dielectric properties over the studied frequency range, suggesting its possible application in tuneable matching networks and frequency agile antennas. Electrical properties study suggested a non-Debye type electrical response with a thermally activated conduction mechanism occurring in the material. The dependence of conductivity with temperature showed negative temperature coefficient of temperature behaviour of the compound and the ac conductivity spectrum followed Johnscher's power law. The variation of exponent with temperature suggested correlated barrier hopping conduction mechanism in the material. [ABSTRACT FROM AUTHOR]