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Detecting and monitoring hydrogen peroxide (H2O2) levels is crucial across various industries due to its potential health hazards at elevated concentrations. Hence, there's an urgent need for cost-effective, rapid, and straightforward analytical methods for H2O2 detection and monitoring. This study introduces a simple synthesis method for Barium Titanate (BaTiO3) and Molybdenum disulfide (MoS2) (BaTiO3/MS) nanocomposite via mechanochemical means. The nanocomposite exhibits remarkable peroxidase-like activity, catalyzing the oxidation of TMB (3,3',5,5'-tetramethylbenzidine) in the presence of H2O2. This catalytic reaction results in the formation of a blue-colored solution with an absorbance peak at 652 nm. The increase in absorbance, facilitated by the catalytic properties of BaTiO3/MS enables precise detection of H2O2 with a detection limit of 8.0 µM. Furthermore, a modified filter paper incorporating the nanocomposite and agarose gel with TMB was developed. The change in color intensity of the filter paper upon exposure to H2O2 was observed and quantified in terms of RGB (Red Green Blue) values using an Android smartphone-based software Color Meter as well as Windows-based software ImageJ. Both the programs gave nearly similar RGB values. This paper-based sensor eliminates the reliance on a UV-visible spectrophotometer, making it portable and user-friendly. This study presents a novel approach for optical and colorimetric detection, with the potential to advance sensing devices for various analytes. [ABSTRACT FROM AUTHOR]

Detecting and monitoring hydrogen peroxide (H2O2) levels is crucial across various industries due to its potential health hazards at elevated concentrations. Hence, there's an urgent need for cost-effective, rapid, and straightforward analytical methods for H2O2 detection and monitoring. This study introduces a simple synthesis method for Barium Titanate (BaTiO3) and Molybdenum disulfide (MoS2) (BaTiO3/MS) nanocomposite via mechanochemical means. The nanocomposite exhibits remarkable peroxidase-like activity, catalyzing the oxidation of TMB (3,3',5,5'-tetramethylbenzidine) in the presence of H2O2. This catalytic reaction results in the formation of a blue-colored solution with an absorbance peak at 652 nm. The increase in absorbance, facilitated by the catalytic properties of BaTiO3/MS enables precise detection of H2O2 with a detection limit of 8.0 µM. Furthermore, a modified filter paper incorporating the nanocomposite and agarose gel with TMB was developed. The change in color intensity of the filter paper upon exposure to H2O2 was observed and quantified in terms of RGB (Red Green Blue) values using an Android smartphone-based software Color Meter as well as Windows-based software ImageJ. Both the programs gave nearly similar RGB values. This paper-based sensor eliminates the reliance on a UV-visible spectrophotometer, making it portable and user-friendly. This study presents a novel approach for optical and colorimetric detection, with the potential to advance sensing devices for various analytes. [ABSTRACT FROM AUTHOR]

Tunnel field effect transistor (TFET) is a gate-controlled, quantum FET device, exhibiting band-to-band tunneling (BTBT) transport phenomena with lower subthreshold swing (SS) than bulk MOSFET devices. Low ON-state current (ION) is an inherent problem with TFET devices. Various research groups are working to address the limitations due to low ON-state current and for performance improvement of the device. The work in this paper is an attempt to overcome the low switching current issue by using ferroelectric material (Fe), barium titanate (BaTiO3) in conventional double gate TFET, having Si1-xGex/Si semiconductors configuration. In the proposed TFET device, the high-κ dielectric HfO2 is replaced by BaTiO3, ferroelectric material (Fe) in the source region. The replacement of HfO2 gate materials by BaTiO3 Fe is found to improve ION (~ order of 10−8 A/µm -to-10−5 A/µm). The FeDGTFET device shows ~ 103 times improvement in ION with unaffected IOFF (~ 10−20 A/µm). In circuit and system design figure of merit, optimization is a critical task for designers. The work in this paper is divided into three sections. Initially, two structures based on high-κ, one with only high-κ (HfO2) DGTFET and the other one based on HfO2 and ferroelectric material BaTiO3 (FeDGTFET), are compared. Analysis of the electric parameters of the two structures shows the performance advantage of the structure based on the ferroelectric material. Next, a parametric study of the FeDGTFET structure is performed linking Silvaco Atlas with MATLAB to analyze the electrical parameters of FeDGTFET. Finally, an optimization technique called algorithm genetic 'AG' is employed to show enhancement in the ION current from 10−5 to 10−4A/µm without affecting the IOFF. [ABSTRACT FROM AUTHOR]

Understanding space charge dynamics in cross-linked polyethylene (XLPE) is crucial for optimizing electrical insulation systems, preventing insulation failure, and ensuring the reliable performance of electrical equipment. Research is focused on advanced characterization techniques and predictive models to mitigate space charge effects, which are key factors in the aging and degradation of high-voltage polymer insulators. While experimental measurements are common, theoretical models are less so. This paper investigates the dynamics of space charges in barium titanate (BaTiO3)-doped XLPE nanocomposites under a continuous electric field using the bipolar charge transport model. The results show that doping with BaTiO3 significantly improves the dielectric properties of XLPE. The study presents and discusses the evolution of the electric field and charge density over time for different types of charges. [ABSTRACT FROM AUTHOR]

In this paper, free vibration analysis and temperature-dependent buckling behavior of porous functionally graded magneto-electro-thermo-elastic material consisting of cobalt ferrite and barium titanate were modeled and analyzed. A high-order sinusoidal shear deformation theory was used to accurately model the anisotropic material behavior. The study examined the porosity role variation across thickness in the buckling and free vibration behavior of nanobeams, as well as the effects of magneto-electro-elastic coupling, thermal stresses, nonlocal properties, externally applied electric and magnetic field potential, and porosity volume fraction. [ABSTRACT FROM AUTHOR]

Purpose: The present paper focuses on the propagation behaviour of Shear Horizontal (SH) waves in a fluid-saturated functionally graded fractured porous material layer consisting of sedimentary rocks perfectly bonded to an irregular piezoelectric semi-infinite substrate with flexoelectric effect. Two distinct cases corresponding to two differently shaped irregularities, viz. rectangular and parabolic, are considered at the layer-substrate interface. Methods: With the help of Fourier transform, inverse Fourier transform, and perturbation technique, complex frequency relation has been derived for each type of irregular interface. Two different flexoelectric materials, viz. Lithium niobate (LiNbO 3) and Barium titanate (BaTiO 3) , are taken into account for performing comparative graphical analysis. Results: Obtained frequency relations are dissociated into real and imaginary components representing the dispersion and damping of SH-wave propagation. Dispersion and attenuation characteristics of SH-waves are executed graphically on the basis of several key parameters, such as irregularity, functional gradient, flexoelectric coefficient, volume fraction of matrix and fracture pores, piezoelectric, and dielectric constants. Conclusions: On applying the referred conditions, the dispersion equations for both type of irregularities fairly match with the Classical Love wave equation. This fact validates the consideration of the layered composite structures. The noteworthy effects of the key parameters on the dispersion and damping of SH-waves are revealed graphically. Moreover, the phase and damped velocities of SH-waves are observed to be significantly greater for LiNbO 3 than for BaTiO 3 in each irregular case. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis bacteria is an illness that affects many people worldwide. Early diagnosis is crucial for patient care and can lower the death rate. As a result, sensitive and rapid detection of mycobacterium tuberculosis bacteria in the blood is crucial. In this paper, a novel surface plasmon resonance (SPRE) sensor consisting of a coupling prism, silver (Ag), barium titanate (BaTiO3) and graphene (Gr) layers is presented. The transfer matrix (TM) technique is used for the analysis of the SPRE structure. The Ag and BaTiO3 thicknesses and the number of Gr sheets are optimized to get the highest sensitivity of the proposed SPRE biosensor. The full width at half maximum (FWHM), detection accuracy (DA) and figure of merit (FOM) are investigated. The best performance has been obtained with 65 nm (Ag), and 9 nm (BaTiO3). The number of Gr layers is investigated and optimized to two layers. The highest sensitivity of 300 deg./RIU has been obtained for the proposed SPRE biosensor when the optimized thicknesses are employed. Compared with existing SPRE biosensors in the literature, the proposed sensor exhibits greater sensitivity. The excellent performance makes this SPRE-based sensor promising to be used in numerous biosensing applications. [ABSTRACT FROM AUTHOR]

It has been reported that the size of barium titanate (BaTiO3, BT) fillers plays an important part in the dielectric properties of the dielectric composites using polymer as a matrix and BT ceramics powders as fillers. However, BT nanoparticles are usually used as fillers. In addition, compared with conventional hot-pressing technology, UV-curing technology has many advantages, such as high efficiency, energy saving and environmental protection. In this paper, composites containing epoxy acrylic (EA) as a matrix and BT powders with various diameters of 3 μm, 0.5 μm and 60 nm as fillers are manufactured by using the UV-curing technique. The influence of BT size on the dielectric performance of BT/EA composites is investigated. BT(0.5 μm)/EA composites show the highest dielectric permittivity, which is 24.10 with a BT fraction of 25% at 50 Hz. BT(3 μm)/EA composites show the lowest dielectric loss tangent, which is 0.114 with a BT fraction of 25% at 50 Hz. BT(0.5 μm)/EA composites possess the highest breakdown strength, the α value of which is 147 when the BT fraction is 25%. In conclusion, by adjusting the BT size and filling degree, BT/EA composites can be prepared with the expected dielectric parameters. [ABSTRACT FROM AUTHOR]

The effects of sintering temperature on the structural, dielectric, and ferroelectric properties of lead-free Ba0.96Nd0.02Na0.02TiO3 ceramics fabricated via a conventional solid-state reaction process are discussed in this paper. Sintered temperatures for the ceramics were 1200 °C, 1250 °C, 1300 °C, and 1350 °C. All samples comprise a single-phase tetragonal structure, according to XRD, Rietveld refinement, and Raman spectra. The density of electrons Equivalence maps was visible on Fourier maps. As the sintering temperature increases from 1200 to 1300 °C, the grain size increases from 4.64 to 9.84 µm. The correlation between structural, morphological, dielectric, and ferroelectric properties is detailed. The temperature dependency of the dielectric constant has been studied at three different frequencies in temperatures ranging from 30 to 200 °C. At 1300 °C, the Ba0.96Nd0.02Na0.02TiO3 ceramic achieves an optimum dielectric constant of 1054 and a dielectric loss of 0.012. Furthermore, at 1300 °C, this sintered material performs excellent ferroelectric remnant polarization of 8.05 µC.cm−2 and a coercive field of 20.87 kV.cm−1. Interestingly, the loss tangent at different frequencies for 1300 °C sintered samples was less than 0.1 over the entire temperature range, indicating that this sample is suitable for Multilayer Ceramic Capacitors (MLCCs) used in high-temperature applications. [ABSTRACT FROM AUTHOR]

This paper presents the modeling of a novel Kron-5 (K5) prism-based Surface Plasmon Resonance (SPR) sensor to detect urea employing Aluminum arsenide (AlAs). The proposed SPR structure is designed based on a silver (Ag)-coated Kretschmann configuration. This structure contains AlAs to avoid Ag oxidation, as well as barium titanate for increased absorption, and black phosphorus for biorecognition element, respectively. For the detection process, the urea concentration of 0.625 gm/dl, 2.5 gm/dl and 5 gm/dl are used with the refractive indices (RIs) of 1.337. 1.339 and 1.342, respectively. The presented work is shown in three significant ways at 633 nm wavelength by exploiting the transfer matrix method. Firstly, the optimal performance of the proposed K5 prism-based structure is compared with BK7 and SK11-based structures, which have lower and higher refractive indexes compared to the proposed prism. Secondly, the optimal performance of the proposed structure is validated with respect to the RI of urea. Thirdly, an impact of AlAs in the proposed structure has been shown. The maximum achieved SPR parameters are sensitivity of 452.85°/RIU, quality factor of 93.37 RIU - 1 , detection accuracy of 0.65 and dip-of-figure-of-merit of 129,388.57 for the proposed sensor. Finally, the comparative study of SPR sensor performance for urea detection is presented. [ABSTRACT FROM AUTHOR]

The distribution of functional filers in polymer matrix composites has a decisive effect on the material properties, however, functional fillers cannot be distributed in an orderly way and orientation in the polymerization system under natural conditions. It was found that the application of external field in the preparation process of materials can effectively improve the dispersion of functional fillers, and induce the orderly orientation of functional fillers, which can endow polymer matrix composites with excellent properties. In this paper, a novel core–shell structural nanorod with magnetic rod-shaped zinc ferrite (ZnFe2O4)(R-ZFO) as core and barium titanate (BaTiO3)(BT) as shell was successfully prepared by sol gel method. Then this core–shell nanorod were doped into the polyvinylidene fluoride-co-hexafluoropropylene (P(VDF-HFP)) to prepare the composites. The arrangement of ZnFe2O4@BaTiO3 nanorod in P(VDF-HFP) was controlled by a parallel magnetic field during the hot-press to obtain an ordered directional arrangement. The microstructure and properties of composites were investigated and the orientation effects of ZnFe2O4@BaTiO3 along the electric field orientation on the dielectric performance of P(VDF-HFP) composites were also analyzed. Results showed that ZnFe2O4@BaTiO3 prepared in this experiment are composed of a core–shell particle with a magnetic core and a dielectric shell, the core–shell particle can turn under the action of a magnetic field, thus forming an oriented structure in the composite film. The dielectric properties of ZnFe2O4@BaTiO3-P(VDF-HFP) composites were related to the anisotropy of ZnFe2O4@BaTiO3. When the orientation of ZnFe2O4@BaTiO3 is parallel to the electric field, the highest dielectric constant of the polymer composite with 80 vol% ZnFe2O4@BaTiO3 reaches as high as 27.77 at 100 Hz, which is 28% higher than that of the non-oriented polymer and 113% higher than that of the pure polymer. when the filling ratio is 40 vol%, the energy storage density of ZnFe2O4@BaTiO3-P(VDF-HFP) composites is 1.18 higher than that of non-oriented composites and 1.32 times higher than that of polymer matrix. This experiment proves that the magnetic core–shell particles can be oriented by the external magnetic field, and this orientation structure can improve the dielectric properties of the composite. [ABSTRACT FROM AUTHOR]

In this paper, the multi-phase ceramic composites, consisting of dielectric barium titanate BaTiO3 (BTO) and rare-earth-doped magnetic spinel ferrite NiFe2–xSmxO4 (NFSO) with x = 0.00, 0.10, and 0.20 were synthesized through solid-state route. The structure of the prepared samples has been examined through XRD. The results indicate the occurrence of both perovskite (BaTiO3) and spinel (NiFe2–xSmxO4) phases in the prepared composites.The magnetic as well as dielectric properties of the prepared samples were investigated and P–E hysteresis loops were recorded at various voltages. It has been found that the higher Sm concentration composite exhibits high dielectric permittivity (~ 9200) along with high remnant polarization (0.54 μC/cm2) and low saturation magnetization (12 emu/g) at room temperature. The analysis showed that the ferrite phase (NFS0) has influenced the magnetic properties and dielectric response of BaTiO3 material. [ABSTRACT FROM AUTHOR]

In this paper, we report a theoretical study of the structural, electronic, thermoelectric and piezoelectric properties of TaXSn (X = Co, Rh and Ir) half-Heusler compounds crystallizing with cubic MgAgAs-type structure. We have made a quantitative evaluation of thermoelectric figure of merit (ZT) and the electromechanical coupling coefficient (k14) of these compounds. Accordingly, we intend to combine the first-principles band structure calculations using (DFT)-based FP-LAPW approach and the semi-classical Boltzmann transport theory within constant scattering time approximation (CSTA) to interpret and predict the thermoelectric performance (ZTe) without the lattice thermal conductivity as a function of the chemical potential at various temperatures. Further, to obtain a reasonable estimate for (ZT) with the intrinsic lattice thermal conductivity, we have calculated the relaxation time (τ) at various temperatures using Bardeen–Shockley theory. Finally, for predicting piezoelectric coefficients, we have employed the modern theory of polarization as provided by density-functional perturbation theory (DFPT) based on plane waves and pseudo-potentials (PP-PW). Our key result is that these half-Heusler semiconductors are attractive for practical applications in energy-harvesting technology, which has a high (ZT) and (k14) of 0.89 and 0.25, respectively, at room temperature. [ABSTRACT FROM AUTHOR]

A smart-structure variant representing a piecewise homogeneous body composed of elastic and viscoelastic materials and piezoelectric elements the electrodes of which can be connected to shunting circuits is considered. One of the basic purposes of such structures is vibration damping. This paper deals with a variant in which the classic resistor in a shunting circuit is replaced by a graphene composite acting not only as a mechanically deformable body, but also as a resistor in a smart structure. The mathematical formulation of the problem of forced steady-state and natural vibrations in the structures composed of elastic and viscoelastic elements, piezoelectric elements, and graphene composites acting as a deformable body and a resistor is given. The results of numerical experiments demonstrate the applicability of graphene composites for implementing an additional mechanism of vibration damping in smart structures based on piezoelectric elements. [ABSTRACT FROM AUTHOR]

In this paper, undoped BaBi2−x−yNb2ErxYbyO9 (BBN), Er3+ doped BBN, and a series of Er3+/Yb3+ co-doped BBN ferroelectric ceramic is synthesized by the solid-state method to study the structural, dielectric, ferroelectric, and energy storage behavior of the prepared ceramic. XRD spectra revealed orthorhombic geometry and Fmmm phase group of each prepared ceramic. SEM micrograph shows dense microstructures similar to square-shaped structures. Two FTIR bands at 619 and 822 cm−1 are observed, displaying the characteristic peaks of the Aurivillius phase. Four Raman bands are detected for undoped BBN, while twelve are visible in Er3+/Yb3+ doped BBN compositions. Further, this work utilizes a comparable method to correlate Nb–O stretching frequencies with their corresponding bond lengths using Herschbach's exponential function. Temperature-dependent dielectric studies show considerable dispersion below and above maximum temperature (Tm), and the dielectric constant (εʹ) decreases with an increase in frequency. The dielectric loss (ɛʺ) curves are quite diffused, and shifts in the maxima with frequency have been observed, thus validating the relaxor behavior of all the prepared BBN compositions. The slimmer PE curves were obtained under moderate electric fields ranging from 75 to 100 kV/cm. The energy storage parameters (W, Wrec, η) are improved with increasing applied electric field. The energy storage efficiency (η) obtained for undoped, Er3+ doped, and Er3+/Yb3+ co-doped BBN ceramics are 78.25%, 83.39%, and 90.87%, respectively. The energy storage parameters revealed good temperature stability from 303 to 415 K, indicating that the synthesized material might aid in developing modern electronic equipment for energy storage applications. [ABSTRACT FROM AUTHOR]

Detection of water impurities is an important issue in many applications, especially in the medical field. In this paper, a fiber optic sensor based on surface plasmon resonance has been numerically simulated and is used for detecting 10% glucose (called dextrose 10%). This sensor consists of two layers, the first layer is metal such as cobalt, nickel, platinum, and silver and the second layer is barium titanate. The sensor performance parameters were calculated using the normalized transmitted power in three different values of 300, 600, and 900 microns of fiber core diameter. Ag/BaTiO3 with 900 microns fiber core is the most qualified structure. In the second part of the research, the effect of aluminum–silver alloy has been investigated to enhance the quality factor of Ag/BaTiO3. The combination ratio of Ag–Al (0.1:0.9) was the best choice to increase the quality factor of the sensor from 62.46 (RIU-1) to 88.0 (RIU-1). [ABSTRACT FROM AUTHOR]

In this article, a highly sensitive surface plasmon resonance biomedical sensor based on barium titanate, MXene and nickel hybrid nanostructure has been reported. The present paper is based on a modified Kretschmann configuration. In this configuration, multilayers are vertically stacked together to improve the optical and electronic properties of the proposed surface plasmon resonance sensor. Barium titanate and MXene have unique properties like large surface area, chemical stability, tunable bandgap, small work function, layered structure and good matter-light interaction to improve the performance parameters of the proposed surface plasmon resonance sensor. Nickel also plays a vital role to enhance the performance parameters because it has high metallic conductivity, a large number of absorption sites and hydrophilicity. The optimized performance parameters are angular sensitivity (3160RIU−1), detection accuracy (0.3072 deg−1), figure of merit (97.075 RIU−1) and limit of detection (3.164 × 10−6) for CaF2 prism/Ag/BaTiO3/Ni/MXene/Sensing medium at 633 nm wavelength. The strong transverse magnetic field intensity is also plotted for the biomedical sensor to analyze the penetration depth. The designed surface plasmon resonance sensor's optimal penetration depth into the sensing medium is 137 nm. The above results will open a new way to design and develop such type of surface plasmon resonance biomedical sensor. [ABSTRACT FROM AUTHOR]

This paper takes KNN ceramics as the research object, and introduces the second component of ABO3 type perovskite structure into it. A series of (1-x)K0.5Na0.5NbO3-xBa(Mg1/3Ta2/3)O3(x = 0.02, 0.03, 0.04, 0.05, 0.06, 0.07) (KNN-xBMT) nanostructured ferroelectric transparent ceramics were successfully synthesized by solid-phase reaction. The effects of BMT on the optical permeability, phase transition, microstructure and electrical properties of KNN ceramics were systematically studied. It is found that when the BMT content x = 0.05, the transmittance of the ceramic at 1100 nm wavelength reached 68%, and ceramic has the smallest grain size and a concentrated grain size distribution range. Compared with pure KNN ceramics, these nanostructured ceramics have better optical transmittance. The formation of pseudo-cubic phase in ceramics at x ≥ 0.04 promotes the enhanced relaxation of ceramics, and the hysteresis loop becomes elongated. The maximum polarization (Pm) of the ceramics is reduced, and the energy storage efficiency (η) reaches a maximum of 65%. When the BMT content x is over 0.04, the two peaks in the dielectric temperature spectrum gradually merged with the increase of BMT content, and the phase transition temperature (Tm) shifted to low temperature. This shows that the BMT addition increases the relaxivity of the ceramics. [ABSTRACT FROM AUTHOR]

In this paper, the electrospinning of Polyvinylidene hexafluoropropylene (P(VDF-HFP)) composite nanofibers was performed by adding rare earth complexes Eu(TTA)3(TPPO)2 and FeCl3·6H2O as fillers. The effects of Eu(TTA)3(TPPO)2 and FeCl3·6H2O fillers on the morphology, crystal structure, thermal properties, and fluorescence properties of P(VDF-HFP) composite nanofibers were investigated by the scanning electron microscopy, Fourier transform infrared spectroscopy, atomic force microscopy, X-ray diffraction, and differential scanning calorimetry and fluorescence. The mechanical properties, sensitivity, ferroelectric properties, and piezoelectric output of monolayer and sandwich structure composite nanofiber membranes used as sensors were studied. The results show that the synergistic effect of double fillers increases the content of β-phase with piezoelectric properties by nearly 20%, reaching 96.9%. The sandwich structure of the PU/P(VDF-HFP)-Eu(TTA)3(TPPO)2-FeCl3·6H2O/PU flexible sensor has high sensitivity (~ 0.29 kPa− 1), high piezoelectric output (~ 3.7 V), high strain (~ 230%), and fluorescence characteristics. It is expected to be applied in wearable flexible sensors, photoelectric devices, and other fields. [ABSTRACT FROM AUTHOR]

In this paper, a negative temperature coefficient (NTC) thermistor material Co1.7Ni1.3−xAlxO4 (0 ≤ x ≤ 0.5) with high resistivity and low B-value is investigated for low temperature applications. The Co1.7Ni1.3−xAlxO4 ceramics consist of a Ni-rich rock salt phase and a tetragonal spinel phase formed by the decomposition of the cubic spinel phase. With increasing Al content, NiO is reabsorbed into the spinel lattice. The added Al does not affect the crystal structure and forms a solid solution with the decomposed phase. Because of the introduction of Al, the number of carriers involved in the conductivity decreases and the hopping distance and hopping frequency both decrease, thus increasing the resistivity. In the studied range, the B25/50 value increases slightly with increasing Al content from 1711 K to 2496 K, while the resistivity increases from 4219 Ω cm (x = 0) to a maximum value of 43484 Ω cm (x = 0.3), then decreases to 21233 Ω cm (x = 0.4) and finally increases to 25213 Ω cm (x = 0.5). [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride) (PVDF) displays ferroelectric, piezoelectric and pyroelectric behavior and it is widely used in high-tech applications including sensors, transducers, energy harvesting devices and actuators. The crystallization of this polymer into highly polar β phase is desirable but is hard to achieve without applying specific thermo-mechanical treatments. Indeed, fabrication processes directly affect PVDF molecular chain conformation, inducing distinct polymorphs. In this paper, we present the fabrication of PVDF/BaTiO3 composite foams by thermally induced phase separation method (TIPS). Different compositions are tested and characterized. The crystallinity, and in particular the development of electroactive β crystal phase is monitored by FTIR, DSC and XRD measurements. Dielectric properties are also evaluated. It turns out that TIPS is a straightforward method that clearly promotes the spontaneous growth of the β phase in PVDF and its composite foams, without the need to apply additional treatments, and also significantly improves the degree of crystallinity. BaTiO3 content gives additional value to the development of β phase and total crystallinity of the systems. The low permittivity values (between 2 and 3), combined with the cellular morphology makes these materials suitable as lightweight components of microelectronic circuits. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

In this paper, tetragonal barium titanate (BaTiO3) nanopowders were synthesized by a new wet chemical route named sol-hydrothermal method. The effects of different temperatures, time and raw materials on the properties of BaTiO3 were studied. The results showed that BaTiO3 was not formed in the precursors. All powders were pure perovskite phase except for the powder prepared using BaCl2 as raw material at 100 °C. The main morphology of the powders was near-spherical. With the increase of hydrothermal temperature and time, the agglomeration decreased, the crystallinity and the tetragonal content increased for the powders. The optimal conditions of tetragonal BaTiO3 nanopowders synthesized by different raw materials were 120 °C (BaCl2), 140 °C (BaAc2) and 160 °C for 24 h [Ba(NO3)2], respectively. The size of the powders prepared by optimal conditions ranges of 125 nm ~ 250 nm in diameter. Moreover, a possible formation mechanism was proposed for BaTiO3 nanopowders synthesized by the sol-hydrothermal method. The as-prepared tetragonal BaTiO3 powders could be used as medium material for multilayer ceramic capacitors. [ABSTRACT FROM AUTHOR]

The discovery of the dopant effects on BaTiO3 has attracted great interest after a compound of 50(BaTi0.8Zr0.2O3)–50(Ba0.7Ca0.3TiO3) system exhibited extraordinarily high piezoelectric properties (d33 > 600 pC/N). Recently, modifications made on the BaTiO3-based piezoelectric materials, particularly at the A-site, have gained the most attention due to the existence of the morphotropic phase boundary (MPB) region. In this paper, we reviewed several dopants that have been extensively used to enhance the piezoelectric and dielectric properties of a BaTiO3 such as Sn and Zr. A ternary triangle of BaTiO3–BaSnO3–BaZrO3 is used to evaluate the correlations between the changes in the Sn- and/or Zr-doped BaTiO3 piezoelectric ceramic properties. The structural changes that have been affected by the dopant contents were also comprehensively reviewed. There is clear evidence that the dopants significantly affect the intrinsic properties of the BaTiO3-based ceramic materials. The dielectric constant εr value increases from 1900 to ~ 6000 at room temperature, while the piezoelectric constant d33 value is also increased from 191 pC/N to ~ 600 pC/N. All the compositions described in this review were prepared by using a conventional solid-state route. [ABSTRACT FROM AUTHOR]

Yttrium iron garnet (YIG) (Y3Fe5O12) films have been grown on single-crystal lithium niobate (LiNbO3) ferroelectric substrates by ion beam sputter deposition. X-ray diffraction, electron microscopy, magnetic measurement, and spin wave propagation results for the Y3Fe5O12 films suggest that they can be used in devices for mutual conversion of magnetic and electrical quantities. [ABSTRACT FROM AUTHOR]

This paper offers a simple, low-cost, and effective method to prepare high-performance dielectric elastomer. 4-chorophenethyl alcohol as dipole functionalizes crosslinker and then the functional crosslinker is utilized to prepare a novel dipolar silicone elastomer (SRCl). The introduction of dipole reduces regular arrangements of molecular chains and the dispersive crosslinking is formed in SRCl. The dipolar crosslinkers are evenly distributed in the crosslinking network, so the mechanical, dielectric, and electromechanical properties are improved. The dielectric elastomer actuator made of the SRCl with 15% dipoles exhibits a maximum actuated strain of 9.97% and the SRCl with 12% dipoles shows the highest breakdown field strength of 73.33 V/μm, which is increased by 156% and 52%, respectively, compared with pure silicone elastomer (SR, 3.89% at 48.23 V/μm). In addition, barium titanate (BT) nanoparticles as filler is mixed with SRCl to prepare the SRCl/BT composites. It is found that the dielectric property of composites is dominated by the matrix polarity. The electrostatic interaction between hydroxyl groups on BT nanoparticles and chlorine groups on the SRCl matrix improves the dispersion of BT nanoparticles in SRCl matrix. The maximum actuated strain of SRCl/20% BT (11.97%) is 3 times as high as SR (3.89%). [ABSTRACT FROM AUTHOR]

The present paper reports the investigation of structural, electrical, dielectric, and transport properties of the polyethylene oxide (PEO)-based polymer nanocomposite (PNC), with sodium hexafluorophosphate (NaPF6) salt and barium titanate (BaTiO3) as nanofillers. The PNC has been prepared via standard solution casting technique. The structural investigation has been investigated by X-ray diffraction and evidence the enhancement in amorphous content. The morphology has been examined by Field emission scanning electron microscopy technique and confirms the composite formation. The presence of polymer–ion and ion–ion interaction has been confirmed by the Fourier transform infrared spectra (FTIR) and evidences the PNC formation. The impedance spectroscopy has been performed to evaluate the ionic conductivity in the temperature range 40–100 °C. The increase of conductivity is obtained with the addition of nanofiller and temperature-dependent conductivity follows Arrhenius behavior. The PNC film having the highest conductivity exhibits low activation energy and indicates the fast ion migration. The ion transference number is close to unity and the voltage stability window is within the desirable limit. The complex permittivity and complex conductivity have been obtained and the plot has been fitted in the whole frequency window. The fitted plot is in perfect agreement with experimental data. The PNC having the highest conductivity has high dielectric strength and low relaxation time. It confirms the nanofiller role in enhancing ion migration. The ion transport parameters (n, μ, D) are also in correlation with impedance and dielectric analysis. The optimized PNC films have been used to prepare the Electric double-layer capacitors (EDLC) and it demonstrates the improved performance which may be attributed to the effective role played by nanofiller in boosting ion dynamics. [ABSTRACT FROM AUTHOR]

In this paper, an acoustic sensor having ZnO based circular diaphragm sandwiched between two aluminum electrodes as the key element that can find applications in energy harvesting from acoustic sources has been designed, modeled, simulated, fabricated and tested. The ZnO layer is RF sputtered on Silicon substrate and a cavity has been formed by back etching the substrate. The dimensions of the structure are chosen such that the natural frequency of the structure closely matches with that of source frequency to get maximum output voltage due to resonance. The structure is mathematically modeled by Lumped Element Model method and simulated with Finite Element Model method. The experimental results indicate approximately 40 mV output voltage (Open circuit) at 140 db and the natural frequency in the range 11–12 kHz which is in close approximation with the results in mathematical model and simulated structure. [ABSTRACT FROM AUTHOR]

The paper proposes a microstructural model of tetragonal single-crystalline barium titanate for analyzing how the state of its domain structure can influence the simulation accuracy of dielectric hysteresis curves with regard for domain interactions and for stress and electric field inhomogeneities in the single crystal. Hysteresis curves based on finite element homogenization are presented for all eight types of second-rank laminate domain patterns satisfying the compatibility conditions. It is shown that the properties of domain structures are substantially anisotropic under loading in different directions and that the dielectric hysteresis for different domain patterns differs greatly. The proposed model allows one to describe the effects of domain hardening and unloading nonlinearity. The results of calculations using the model agree well with experimental data at different cyclic load amplitudes. [ABSTRACT FROM AUTHOR]

In this study, the relationship between core electron energy band changes and chemical changes occurring at the site of positron annihilation in BaTiO3(BTO) doped by different amounts of metallic element Eu was investigated by Coincidence Doppler broadening spectroscopy. The reduction of the background spectrum caused by a simultaneous detection system in Doppler broadening spectroscopy makes it possible to investigate the contribution of high-momentum core electrons in the process of positron annihilation in the BTO: Eu structure. The results obtained from the spectrum in the range of momenta up to 15 × 10− 3 m0c show that with increasing Eu, the contribution of valence electrons in the process of positron annihilation increases, but at higher momenta of the sample containing 0.05 europium compared to the samples containing 0.01 and 0.03% impurity, a higher contribution in the ratio curve in the annihilation process was observed. [ABSTRACT FROM AUTHOR]

Composite dielectrics with excellent electrical properties are integral to today's energy industries and power infrastructure. Epoxy resin filled with inorganic nano-fillers has been extensively studied for its excellent performances. In this paper, barium titanate (BaTiO3) nanoparticles are selected as the fillers and fluorinated by plasma treatment. The morphology, element content and chemical bond of BaTiO3 and fluorinated BaTiO3 fillers are characterized by SEM, EDS, XPS and FTIR, respectively. The influence of filler concentration and fluorination on flashover voltage of epoxy resin composites was studied. We found that the fluorinated BTO could improve the compatibility of filler and matrix and surface insulation of epoxy resin composites. Finally, the relationship between filler concentration, dielectric constant, fluorination treatment and charge dissipation was analyzed, and the trap distribution on the surface of composites was calculated by isothermal surface potential decay method. Fluorinated BaTiO3 particles as fillers blended with epoxy resin have great engineering application potential. [ABSTRACT FROM AUTHOR]

Here, in this paper, we have reported the structural, microstructural, optical, ferroelectric and magnetic properties of Nd and W/Co co-substituted Bi4NdTi3−2x(W/Co2)xFeO15 (0.00 ≤ x ≤ 0.15) 4-layered Aurivillius multiferroic ceramics. These ceramics were prepared by conventional high-temperature solid-state reaction method. The room temperature (RT) X-ray diffraction (XRD) and Raman studies revealed that, these ceramics exhibits a pure orthorhombic structure with A21am space group. The surface morphology of these ceramic studies confirmed the formation of randomly oriented grains as non-uniform in size. Further, W/Co2 substitution in BNFT revealed the presence of asymmetrical shaped internal nano-size domains. The band gap of the ceramics was calculated and found to be decreased upon with increasing the concentration of W/Co2. All compounds exhibited improved P–E loops with unsaturated polarization upon substitution with enhance polarization and reduced coercive field. It was found that with higher substitution levels x ≥ 0.10 adversely affected the ferroelectric characteristics. The magnetic measurement revealed that Nd and W/Co co-substitution induced a strong ferromagnetic interaction via Fe3+–O–Co2+/3+ coupling. The high-temperature magnetization studies revealed the Curie temperature (TC) enhances as the W/Co2 concentration increase. Henceforth, the observed outcomes are emphasized for designing new single-phase room temperature multiferroics in future magnetoelectric applications. [ABSTRACT FROM AUTHOR]

In this paper the fabrication of BaTiO3-based thin film heterostructures with ring silver electrodes by low cost deposition techniques was investigated. BaTiO3, Ba1−xSrxTiO3 (x = 0.1, 0.2, 0.3, 0.4) and BaTi1−xZrxO3 (x = 0.1, 0.2) thin films for potential application in microwave technologies were prepared by chemical solution deposition method on Pt-coated silicon substrates and sintered at different temperatures. The prepared films were examined by SEM, AFM, XRD and Raman spectroscopy in order to study the influence of dopants on microstructure and phase changes. Dielectric and ferroelectric properties of the doped BaTiO3 thin films were also investigated to find the optimal composition and structure for tunable application. Complex shaped silver electrodes suitable for measurements of tunability at GHz frequencies were prepared by inkjet printing method. The electrodes with circular shape were printed on the surface of BaTiO3 based thin films by Dimatix inkjet printer. Precision limits of the method and the influence of printing conditions on electrode size and quality were also investigated. [ABSTRACT FROM AUTHOR]

Ba(Ni0.5Nb0.5)O2.75 (BNNO) doped KNbO3 (KN) and (K0.5Na0.5)NbO3 (KNN), abbreviated as KBNNO and KNBNNO, respectively, have been recently reported to co-exhibit narrow band gaps (visible range) and strong piezoelectric/pyroelectric effects simultaneously within the same material. This had never been achieved in a single ceramic material. Such a breakthrough may allure the development of fundamentally novel multi-source energy harvesters based on only one piece of material as well as advanced optoelectronic devices with multiple functions. It has been found that the window of getting the unique combination of these properties is very narrow. Even a slight shifting away from the stoichiometry of the compositions may induce a significant loss of the properties. The reasons are expected to be in the compositions and microstructure of these materials. However, detailed information – e.g. the correlation of the compositions, processing conditions, microstructure and properties – remains to be investigated for such novel materials. In this paper, the inter-influence of different doping amounts of BNNO, calcination and sintering temperatures, phase structures and defects (potassium loss and oxygen vacancy) on the dielectric and ferroelectric properties are studied. The paper reveals the principles and provides guidance to achieving good ferroelectric properties in these emerging perovskite structured materials. [ABSTRACT FROM AUTHOR]

In this paper, the water droplet experimental method was used to in situ study the electrochemical migration and related behaviors of Sn-based lead-free solder. Results showed that the electrochemical migration short-circuit time decreased with voltage increasing. Electrochemical migration was difficult to occur when the voltage was less than 1.5 V. However, when the voltage was above 5 V, metal deposits were generated in a short time and caused a bridge between two electrodes, which led to short circuit. As spacing increased, the short-circuit time prolonged. The three-dimensional pattern between voltage, spacing and short-circuit time had been constructed, which is beneficial to estimate the short-circuit time value under a combination of any voltage and spacing within a certain range. When changed the concentration of NaCl solution, it was founded that dendrites which surface covered much precipitates were formed at a low concentration. At medium concentration, there was no dendrites but only formed a large amount of precipitates. At a high concentration, the dendrites which surface with less precipitates were showed again. The formation mechanisms of dendrites under different NaCl solution concentrations were analyzed. In addition, the effects of different materials on electrochemical migration behavior were also studied, founding that electrochemical migration products of Sn, Sn0.7Cu and Sn3Ag were mainly Sn and Sn oxides. The electrochemical migration products of Sn9Zn contain much Zn element apart from Sn and Sn oxides. At a lower voltage, Sn9Zn solder had better electrochemical migration resistance than Sn, Sn0.7Cu and Sn3Ag, but this phenomenon was not obvious at a higher voltage. [ABSTRACT FROM AUTHOR]

Although BiFeO3-based photovoltaic devices have currently attracted much attention due to their unique physical properties, their practical applications have been limited by the complex and obscure intrinsic physical mechanisms. This paper reported the synthesis of the Ni, Sm co-doped BiFeO3 film capacitors by a spin-coating technology. The results and analysis showed that co-doped BiFeO3 films exhibited low leakage current and well saturated ferroelectric hysteresis loops. Especially, the photovoltaic effect and diode-like effect of ferroelectric film capacitors could be efficiently modulated by the external polarization. The complex intrinsic physical mechanism of photovoltaic effect and diode-like effect under polarization modulation was studied and explained clearly by the energy-band diagram and the theory of ferroelectric polarization. Moreover, the effect of inherent and external factors on photovoltaic output of BiFeO3 films was jointly analyzed by the ferroelectric polarization and photovoltaic mechanism. This theoretical exploration may facilitate to improve the understanding of the photovoltaic effect in ferroelectrics, which will be likely to have the opportunity to advance the design of switchable devices that combine ferroelectric and photovoltaics. [ABSTRACT FROM AUTHOR]

In this paper, the dielectric characteristics of the power transformer oil are enhanced by dispersing newly synthesized nanoparticles. Two nanocrystalline powders, barium titanate (BaTiO3) and nickel ferrite (NiFe2O4), are synthesized via the tartaric acid precursor method. The change in the crystal structure, crystalline size, and microstructure of the synthesized nanoparticles as a function of annealing temperatures are characterized using X-ray diffraction and transmission electron microscope. These nanoparticles are mixed with the transformer oil considering different concentrations such as 25, 50, and 75 mg/l where the sonicator is used to disperse the nanoparticles in the oil samples. The dielectric breakdown strength is tested based on IEC standard. The results confirm the efficiency of the NiFe2O4 than BaTiO3 for enhancing the dielectric characteristics of the power transformer oils. [ABSTRACT FROM AUTHOR]

Negative permittivity has taken off as a research topic in percolative composites recent years. Comparing with the common conductive constituent element in the preparation of metamaterials such as metal, one-dimensional conductive carbon nanotubes (CNTs) provide another choice of functional phase. In this paper, barium titanate (BaTiO3) with multi-walled carbon nanotubes (MWCNTs) uniformly dispersed in the ceramic matrix were prepared by traditional ceramic sintering technology. Field emission scanning electron microscopy, X-ray diffraction and Raman spectroscopy were used to characterize microstructures and phase composition of the metacomposites. With the increasing of CNTs content, the percolation phenomenon of electrical conductivity (9.95 wt%) was found and the conductive mechanism changed because of the formation of conductive MWCNTs networks. Moreover, the negative permittivity behavior was observed when the MWCNTs content reached 7 wt% and the plasma-like negative permittivity behavior could be well explained by the low frequency plasmonic state generated from conductive nanotube networks using the Drude model. [ABSTRACT FROM AUTHOR]

Shaping of ceramics is crucial. Current techniques cannot easily and rapidly shape ceramics without weakening their properties, especially for piezoceramics. We present an ultrafast ceramic shaping method that leverages thermomechanical fields to deform and sinter ceramic powder compacts into complex-shaped ceramics. The shape-forming process hinges on: (1) the implementation of a precise thermal field to activate optimal deformability, and (2) the application of sufficient mechanical loads to guide deformation. We employ a programmable carbon-felt Joule heater that concurrently function as mechanical carriers, effectively transferring applied loads to the ceramic powder compacts. Using this ultrafast shaping and sintering (USS) method, we fabricate barium titanate (BT) piezoceramics in twisted shape, arch shape and with micropatterns. The USS method is energy-friendly (requiring approximately 1.06 kJ mm−3) and time-efficient (in several minutes level). Overall, the USS method offers an effective solution for shaping ceramics and extends them to 3D geometries with enhanced versatility. Shaping ceramics is important for realizing their material properties. Here, the authors modify a Joule heating method to generate morphing thermomechanical fields, guiding the shape formation of ceramics into complex 3D configurations. [ABSTRACT FROM AUTHOR]

Recent works have demonstrated that the optical excitation of crystalline materials with intense narrow-band infrared pulses, tailored to match the frequencies at which the crystal's permittivity approaches close to zero, can drive a permanent reversal of magnetic and ferroelectric ordering. However, the physical mechanism that microscopically underpins this effect remains unclear, as well as the precise role of laser-induced heating and macroscopic strains. Here, we explore how infrared pulses can simultaneously give rise to strong temperature-dependent birefringence and strain in ferroelectric barium titanate. We develop a model of these two coexisting effects, allowing us to use polarization microscopy to disentangle them through their spatial distributions, temporal evolutions and spectral dependencies. We experimentally observe strain-induced patterns that are an order of magnitude larger than that which can be accounted for by laser-induced heating alone, suggesting that non-thermal effects must also play a role. Our results reveal the distinct fingerprints of heat- and strain-induced birefringence, shedding new light on the process of all-optical switching of order parameters in the epsilon-near-zero regime. [ABSTRACT FROM AUTHOR]

In this paper, sandwich structured polyimide hybrid films were prepared by layered coating, in which middle layer is different volume fraction BT/PI monolayer film and both the bottom and the top layers are pure PI. Compared with monolayer hybrid films, sandwich structured hybrid films exert much lower dielectric loss and conductivity, which owe to pure PI layers as insulation layers effective block off conductive paths of middle layer. Besides, the SEM images show hybrid film has obvious layering and without defects. This sandwich structure can redistribute electric field between three layers to optimize breakdown performance, which correspond to data processed by Weibull breakdown distribution. When the intermediary volume fraction is 3 vol%, the breakdown strength of sandwich structured hybrid films is 344.26 kV/mm, which is 1.26 times enhancement than pure PI film. In addition, based on the improvement of the breakdown strength, the energy storage density of hybrid films is improved significantly. When the electric field is 344.26 kV/mm, its energy storage density reached 1.94 J/cm, which is 1.72 times enhancement of pure PI film. [ABSTRACT FROM AUTHOR]

Poling parameters and barium titanate (BT) content significantly affect the piezoelectric and dielectric properties of poly(vinylidene fluoride) (PVDF). Selecting the best possible values for these process parameters is indeed a significant challenge. In this study, piezoelectric nanocomposites for high-energy conversion were prepared by mixing PVDF with BT. The dependence of piezoelectric and dielectric properties on process parameters was investigated. The input parameters, including poling temperature, time and voltage, and BT mass fraction, were considered as input variables. A Box-Behnken Design was used to design and analyze the experiments. ANOVA was performed to study the significance of poling parameters and BT mass fraction. An Artificial Neural Network was used to model PVDF-based nanocomposite properties as a function of the four process parameters. A genetic algorithm was applied to search for the optimal poling conditions and BT mass fraction. The optimal combination leads to a d33 coefficient of 25.259 pC/N, a permittivity of 24.282, and a β-phase fraction (F(β)) of 95.435%. These results were experimentally validated, and the errors were 9.789, 0.338, and 0.305%, respectively. Following the optimization, a PVDF-based nanocomposite with excellent piezoelectric and dielectric properties (d33 = 28pC/N, permittivity = 24.2, F(β) = 95.7%) was fabricated for energy conversion applications. [ABSTRACT FROM AUTHOR]

Electroluminescent (EL) devices are of great significance for expanding the application range of optoelectronics. However, the realization of EL devices with environment-tolerance, stretchability, mechanical cycling stability, self-adhesion, biocompatibility, and high dielectric constant still remains a challenge. Herein, a type of EL device with enhanced comprehensive performances composing of a chlorinated barium titanate/phosphor/polydimethylsiloxane (Cl-BT/phosphor/PDMS) luminescent layer sandwiched between two silver nanowire-cellulose nanocrystal with II crystalline allomorph/Triton X-100 modified polydimethylsiloxane (AgNW-CNC II/TX-PDMS) electrodes fabricated through a full solution-processing strategy is proposed. Environmentally-friendly CNC II with high transmittance acts as an antioxidant, dispersant and film-former for AgNWs. The hydrophilic modification of TX to PDMS imparts the electrodes with self-adhesion, high stretchability, as well as strong interfacial bonding between TX-PDMS and AgNW-CNC II. The electrodes achieve skin-like modulus by adjusting TX content, endowing the EL devices with a high compliance (186 kPa of Young's modulus). The luminescent layer with Cl-BT exhibits a high dielectric constant (19) and luminance (up to 72 cd m−2). The assembled EL device with excellent cyclic stability (luminance retention 85% after 400 cycles), durability (luminance retention >94% after 400 min) and stretchability (88% luminance at 200% strain) can work properly at broad temperatures (−20 ~ 70 °C) and underwater. This biocompatible and self-adhesive EL device demonstrates great potential for implantable biomedical devices and wearable displays under harsh environments. [ABSTRACT FROM AUTHOR]

The influence of cubic and tetragonal systems of nano-sized ceramic barium titanate powder on hemolytic activity, free radical processes and antioxidant activity was studied. The physicochemical properties of BaTiO3 obtained by heat treatment in air at 800°C and 1200°C of the precursor synthesized by the sol-gel method were investigated. Based on X-ray phase analysis in conjunction with Raman spectra and heat capacity measurements, it was found that the crystal structure of BaTiO3 calcined at 1200°C is a tetragonal crystal system, while that of BaTiO3 calcined at 800°C is a cubic crystal system. The analysis of the scanning electron microscopy method in combination with the dynamic light scattering method showed a distribution of nanosized particles from 50 to 250 nm for BaTiO3 at 800°C and from 100 nm to 240 nm at 1200°C. Depending on the processing temperature, the powders were found to have different pore sizes: at 800°C - micropores and at 1200°C - mesopores. [ABSTRACT FROM AUTHOR]

Ceramic/polymer dielectrics with excellent thermal stability and high dielectric performance exhibit great potential in advanced capacitor applications. It is still a major challenge for ceramic/polymer dielectrics to obtain high dielectric constant at low content while maintaining excellent flexibility. To alleviate this issue, here, a flexible polymer dielectric composite consisting of poly(arylene ether nitrile) (PEN) matrix and barium titanate filler coated by Carbon and polypyrone (h-BT@C@PPy) was put forward in this work. The as-prepared composite films displayed high dielectric constant, comparable low loss and favorable interfacial binding due to the hydrogen-bonding interaction between –NH of h-BT@C@PPy and –CN of PEN, effectively promoting the interfacial polarization and remedying the internal interface defects between h-BT and PEN. Consequently, an addition of 8 wt% h-BT@C@PPy into PEN matrix raised the dielectric constant from 3.82 to 13.3 at 1 kHz, while maintaining relatively low dielectric loss (0.05@1 kHz). However, the breakdown strength showed a decreasing trend with the lowest value of 60.37 kV mm−1. Meanwhile, the better flexibility, outstanding thermal stability (the 5% weight loss above 500 °C) as well as excellent permittivity-temperature stability was also delivered by the PEN-based composite films. This strategy furnishes a perspective to design ceramic/polymer dielectrics with high-k achieved at low filler content for the applications of organic film capacitors. [ABSTRACT FROM AUTHOR]

The BaSnO/Ag/BaSnO multilayer structure was designed and fabricated on a quartz glass by magnetron sputtering, followed by an annealing process at a temperature from 150 to 750 °C in air. In this paper, we investigated the influence of the annealing temperature on the structural, optical, and electrical properties of the multilayers and proposed the mechanisms of conduction and transmittance. The maximum value of the figure of merit of 31.8 × 10 Ω was achieved for the BaSnO/Ag/BaSnO multilayer thin films annealed at 150 °C, while the average optical transmittance in the visible ranges was >84 %, the resistivity was 5.71 × 10 Ω cm, and the sheet resistance was 5.57 Ω/sq. When annealed at below 600 °C, the values of resistivity and transmittance of the multilayers were within an acceptable range (resistivity <5.0 × 10 Ω cm, transmittance >80 %). The observed property of the multilayer film is suitable for the application of transparent conductive electrodes. [ABSTRACT FROM AUTHOR]

This paper describes synthesis of the functional BaTiO (BT) nanostructures by composite-hydroxide-mediated (CHM) approach. The effect of processing temperature on the nucleation and the optical, structural properties is investigated. The nanostructures prepared at various temperatures (180, 220 and 250 °C) are thermally stable and nucleate in different morphologies, which shows a temperature-dependent mechanism of the CHM approach. The nanostructures are cubic in nature with an average particle size in the range of 97-250 nm. The local crystal structure investigated by Raman spectroscopy reveals a certain degree of tetragonality on atomic scale in the local phase structure. The micrographs of scanning electron microscopy (SEM) indicate formation of the nanocuboids at 180 and 220 °C with larger particle size. At 250 °C, the product shows ball-like spherical morphology. Energy-dispersive X-ray (EDX) confirms the existence of Ba, Ti and O elements in the product, which indicates a chemically pure product. Further signature on the formation, purity and chemical bonding is obtained from FT-IR spectroscopy. Based on these experimental results, size, morphology manipulation and possible growth mechanisms are proposed with CHM at low temperature and without surfactant. [ABSTRACT FROM AUTHOR]

This paper presents a new structure for the Micro-electromechanical capacitors with high capacitance and tuning range. The obvious feature of the proposed capacitor is the use of a thermal actuator to change the dielectric coefficient of capacitor. In this work, BaTiO is used as a dielectric. Due to its high dielectric coefficient, BaTiO increases the capacitance in this structure. Another characteristic of this material is that it changes the dielectric coefficient linearly in a specified temperature range. Through this work, given the thermal properties of the dielectric, a variable capacitor with a wide tuning range is made using a heater as a thermal actuator. The proposed variable capacitor has a one-piece structure and removes problems such as the pull-in effects completely by eliminating the moving parts. The results show that the tuning range of the proposed capacitor is about 600 % and its capacitance density is equal to 41.66 μF cm. This capacitor can be used in the MEMS telecommunication systems, particularly radars that require high capacity with too small sizes. [ABSTRACT FROM AUTHOR]

Zirconia-based dental implants are in direct contact with living tissues and any improvements in their bioactivity and adhesion to the tissues are highly welcome. In this study, different ratios of barium titanate (BT) were added to 3 mol% yttria-stabilized zirconia (3YSZ) through conventional sintering. The laser-texturing technique was also conducted to improve the biological performance of 3YSZ ceramics. The composition and the surface of the prepared composites were characterized by X-ray diffraction and scanning electron microscopy (SEM), respectively. The roughness and surface wettability of the composites were also measured. Furthermore, MC3T3-E1 pre-osteoblast cells were used for the in vitro experiments. Cell viability was evaluated using a commercial resazurin-based method. Morphology and cellular adhesion were observed using SEM. Based on the results, the laser texturing and the barium titanate content influenced the surface characteristics of the prepared composites. The laser-textured 3YSZ/7 mol% BT composites showed a lower water contact angle compared to the other samples, which indicated superior surface hydrophilicity. The cell viability and cell adhesion of 3YSZ/BT composites increased with the rise in the barium titanate content and laser power. An elongated cell morphology and apatite nucleation were also observed by the BT content. Overall, the laser-treated 3YSZ/5 and 7 mol% BT composites may be promising candidates in hard tissue repair due to their good cell response. [ABSTRACT FROM AUTHOR]

Ba0.97La0.02TiO3 (BLT) ceramic has been prepared by the predictable Molten-Salt process. The structural analyses of the BLT powders were done at room temperature by X-ray powder diffraction. The compound crystallizes with tetragonal symmetry. The dependence of the dielectric constant on temperature for various frequencies (1 kHz–1 MHz) has been determined. The diffuse transition is observed in the variation of the dielectric constant, and it provides evidence for three relaxor characteristics. Three relaxor parts are represented, such as [350 < T < 450; defines relaxor (1), 450 < T < 550; labels relaxor (2), 550 < T < 700; identifies relaxor (3)]. To comprehend the relaxation behavior of the prepared ceramic, three distinct techniques, specifically Debye, Vogel–Fulcher (V–F), and Power low, were utilized. Using the Debye, V–F, and Power law models, the activation energy, Debye frequency, and freezing temperature were derived from the experimental data. The available values are within an acceptable range and provide a clear explanation for the prepared sample's strong relaxation characteristics. The V–F model is found to be more suitable to explain the relaxation process of the prepared ceramic based on the goodness of fit parameter. Characteristically, this study highlights the relaxation process in the lead-free BLT system. [ABSTRACT FROM AUTHOR]