Dielectric Constant Increases Research Articles

Estimation of Structural, Electrical, and Magnetic Variations of Mn-Ni- Zn Ferrites by Substituting Rare Earth Y3+ for High-Frequency Applications

Mn0.3Ni0.3Zn0.4YxFe2-xO4 (x = 0.00, 0.02, 0.05, 0.07, 0.10, 0.15) are synthesize followed by the conventional double sintering ceramic technique. Significant effects of yttrium addition in structural, magnetic, and electric properties of Mn-Ni-Zn ferrite are discussed. The samples are characterized by powder X-ray diffraction (XRD), scanning electron microscopy, vibrating sample magnetometer, and impedance analyzer. XRD pattern reveals that the samples are in simple cubic spinel structure. The microscopic image has confirmed that the average grain size increases with the higher substitution of yttrium. The enhancement of magnetic properties with the addition of yttrium content compared to the un-doped Mn-Ni-Zn ferrite is worth to mention. The frequency and temperature dependence of initial permeability is discussed in the light of magnetic spin canting and grain size of the particles. The excellence of the material from the application perspective can also be noticed from the significant emphasis of the quality factor. Appreciable high saturation magnetization is noticed with the substitution of yttrium that may be owing to the gradual decrease of the Yafet-Kittel angle with the increasing content. A significant increase in dielectric constant associated with the yttrium doping is also observed and reaches a maximum value for the higher substitution of yttrium content.

Response of electrical and dielectric parameters of ZnIn2Te4 thin films to temperature and frequency

ZnIn2Te4 has been synthesized in the bulk form by the melt and gradually cooling method. Then, thermally evaporated thin films have been prepared with different thicknesses (173–385 nm). X-ray diffraction shows X-ray amorphous structure for the prepared films. Energy dispersive X-ray has been used to evaluate the composition of the prepared materials. The temperature dependence of dc and ac conductivities has been studied in the range: 303–413 K. The dc conductivity obeys Mott and Davis model showing semiconducting behavior with two conduction mechanism in this temperature range. Then, dependence of the ac conductivity and dielectric parameters on the frequency has been studied in the range: 1 kHz–1 MHz. Correlated barrier hopping between centers of non-intimate valence alternation pairs is the mechanism describing the response of ac conductivity to the frequency. Both, dielectric loss and dielectric constant increase with increasing the temperature and with decreasing the frequency.

MnO2 as an effective sintering aid for difficult-to-sinter LiTaO3-based ceramics: Densification and dielectric properties

Dense polycrystalline LiTaO3 (LTO) ceramics have rarely been reported due to their poor sinterability, although LTO single crystals are among the well-known piezoelectric and ferroelectric. In this study, LiTaO3-based ceramics with 3 wt% and 5 wt% MnO2 (referred to 3MLT and 5MLT, respectively) are prepared by pressure-less sintering at different temperatures of 1200 °C, 1250 °C, 1300 °C and 1350 °C, respectively, and the effects of sintering temperature on the sinterability, microstructure development and dielectric properties are investigated. The sintered density of the LiTaO3-based ceramics increases significantly at first with increasing of sintering temperature, and then decreases afterwards. Sintered densities of ∼92.6% and 93.1% were achieved for 3MLT and 5MLT sintered at 1250 °C, respectively, and both compositions show a rather homogeneous and well-developed grained microstructure. A moderate amount of MnO2 was entered into the LiTaO3 lattice to form a solid solution, however, Mn3O4 was formed at the grain boundaries and junctions when excess amount of MnO2 added, where the solid solubility is dependent on the sintering temperature. The dielectric properties of both 3MLT and 5MLT ceramics, studied as a function of frequency, show a strong dependence on sintering temperature, where the dielectric constant increases first and then decreases with the increasing of sintering temperature. The dielectric loss first decreases and then increases with the increasing of sintering temperature. Both 3MLT and 5MLT demonstrate a maximum in dielectric constant when sintered at 1250 °C and 1350 °C, respectively. The lowest dielectric loss could be obtained at 1250 °C, which was selected as the optimum sintering temperature for both compositions.

Colossal dielectric constant and ferroelectric investigation of BaTiO3 nano-ceramics

Barium titanate (BaTiO3) nano-ceramics are prepared using nano-ball milling method. Nano-milled samples are calcined at 1200 °C for 6 h to 72 h. Transition from agglomerated growth to fine particles (diameter ~ 350 nm) is observed after nano-ball milling process. Calcination of milled powders at 1200 °C for 6 h and 12 h results in mixed hexagonal and Perovskite BaTiO3 phases. Perovskite phase pure structure is obtained after calcination of 24 h. Further, this phase pure structure is observed to be stable for longer periods of calcination time, i.e., up to 72 h with grain size of ~ 150 nm. Colossal dielectric constant of 1.38 × 106 at log f = 1.3 is observed after calcination for 24 h. Slight increase in dielectric constant, i.e., 2.13 × 106, is observed after calcination for 72 h. Temperature-dependent analyses of sample, calcined at 72 h, exhibit a transition in conduction mechanism at 120 °C. Activation energy of ~ 0.81–1.15 eV is observed for BaTiO3 nano-ceramics. Perovskite BaTiO3 ceramics exhibit saturated ferroelectric hysteresis curves with polarization of 10.28–57.6 μC/cm2. The presence of colossal dielectric constant along with ferroelectricity in BaTiO3 nano-ceramics has potential applications in modern microelectronic devices and for development of novel capacitive data storage devices.

Mechanical and Electrical Properties Investigation of 3D-Printed Acrylonitrile–Butadiene–Styrene Graphene and Carbon Nanocomposites

Acrylonitrile–butadiene–styrene (ABS) nanocomposite filaments for 3D-printing were produced by melt compounding and extrusion. Two types of nanoadditives were employed: (a) graphene nanoplatelets (GnP) at various concentrations and (b) carbon nanotubes (CNTs). Fused filament fabrication (FFF) 3D printer was used for the fabrication of specimens, according to international standards to be employed for the determination of the tension and flexural mechanical properties of the specimens and the correlation with their microstructure. Nanocomposite filaments were also tested in tension, to evaluate the effect of 3D printing on the material. Moreover, the electrical properties of the specimens were also determined. As found out, a decrease in the tensile strength, the tensile modulus of elasticity, the flexural strength, and the flexural modulus of elasticity can be observed with the increase in the GnP concentration, in every case. ABS specimens filled with CNTs exhibited higher tensile and flexural strength and a more brittle behavior when compared to pure ABS and ABS with GnP. Regarding the electrical properties of the composites, it was found that dielectric constant increases by increasing GnP content, the specimens remaining at the same time rather nonconductive, even at a concentration of 10 wt.% in GnP. In contrast, ABS filled with CNTs at a concentration of 10% illustrated a large conductivity.

Structural refinement, investigation of dielectric and magnetic properties of NBT doped BaFe12O19 novel composite system

Currently, it is crucial to develop lead-free multifunctional multiferroic composites for lesser environmental hazards, low cost, and diversified potential applications. We have developed a novel lead free ferrite-ferroelectric composite system with composition (1-x)Na0.5Bi0.5TiO3-(x)BaFe12O19; (x = 0.2, 0.5, 0.8 and 1) via solid-state reaction route. The XRD analysis followed by Rietveld Refinement confirmed the formation of hybrid composites with both ferroelectric and ferromagnetic phases. SEM with EDX and HRTEM used to study the morphology and compositional analysis. The slight changes in cell volume, axial ratio (c/a), bond distances and bond angles confirm lattice-distortion. Low frequency and higher temperature dispersion is observed for both dielectric constant and tangent loss. Moreover, dielectric constant increases up to x = 0.5 and then decreases while tangent loss increases with the addition of BaM. The ac conductivity was found to be increased on increasing frequency, temperature and hexaferrite content in the composites. The dc conductivity curve was found to follow the Arrhenius plot. Room temperature multiferroism is confirmed by P-E, M − H loop and magnetoelectric measurements. Anisotropy constant and field were evaluated from fitted high field M − H loop using the law of approach to saturation (LAS) and both of these and other magnetic parameters found to increase with hexaferrite content. It is observed that Ps and Pr increases with BaM up to x = 0.5 and then decreases. The magnetoelectric coupling coefficient is found to show a maximum value of 2.29 mV/cm.Oe for x = 0.2 sample.

A study of structural and dielectric properties of Ba2+ doped CH3NH3PbI3 crystals

An understanding of the effects of doping in lead perovskites may allow for improved solar cell performance or reduction in toxicity of the materials used. Ba2+ doped CH3NH3PbI3 (CH3NH3Pb1−xBaxI3 with x = 1%, 5% and 10%) are successfully synthesized by cooling down a concentrated aqueous solution containing HI, CH3NH2 and metal acetates and their properties are investigated using x-ray diffraction, differential scanning calorimetry, and impedance spectroscopy (IS). No new structures are formed upon doping with Ba2+ ions, however the lattice expands. The IS measurements show a strong increase in the conductivity and dielectric constants of the doped crystals. The conductivity arises mainly from vacancy mediated iodide ion (I−) migration and the increase in ionic conductivity with dopants is ascribed to increased defect formation due to lattice distortion. In addition, the bulk dielectric constant increases with increasing Ba2+ dopant. The increase in the dielectric constant is consistent with ordering of CH3NH3 dipoles resulting from distortions of the Ba sites in the lattice. The temperature dependence of the dielectric constants is attributed to thermal effects on the orientation of CH3NH3 molecules.

Effects of Sintering Method and BaTiO3 Dopant on the Microstructure and Electric Properties of Bi (Fe0.9Al0.05Yb0.05) O3-Based Ceramics

The (1 − x) Bi (Fe0.9Al0.05Yb0.05) O3–xBaTiO3 (BFAYO-x BTO) ceramics were synthesized by microwave sintering (MWS) and conventional sintering (CS) methods. The crystal structure, surface morphology, dielectric and ferroelectric properties were investigated. XRD patterns show that BTO tetragonal and BFO rhombohedral phases coexist in both MWS and CS samples, and that the diffraction peaks of MWS samples shift to lower angles due to the larger ionic radius of Ba2+ compared with Bi3+. The lattice constant of BFAYO-x BTO ceramics increases with the increase of BTO content. It was found that the average grain size of the MWS ceramic is much smaller than that of the CS ceramic. Dielectric measurements reveal that the dielectric loss and dielectric constant increase with BTO content increasing. The introduction of BTO into BFAYO-based ceramic contribute to the enhancement of the dielectric relaxation behavior. The P–E hysteresis loops demonstrate that the remnant polarization (Pr) and the coercive field (EC) of the MWS samples are smaller than those of the CS samples. Pr and EC first increase, then decrease and then increase again with the increase of BTO content. The maximum and minimum values of the remnant polarization were obtained at x = 0.25 and 0.3, respectively.

EFFECTS OF Co CONCENTRATION ON THE STRUCTURAL AND OPTICAL PROPERTIES OF Zn1−xCoxS FILMS

Amorphous and crystalline Zn[Formula: see text]CoxS ([Formula: see text], 0.3, 0.5) thin films were grown on sapphire (Al2O3) substrates by pulsed laser deposition at substrate temperature of 25∘C and 800∘C, respectively. The X-ray diffraction results show that the crystalline film has a cubic zinc blende structure and the crystalline quality decreased with increasing Co-doping concentration. The X-ray diffraction and X-ray photoelectron spectroscopy spectra reveal that the samples reached an overdoping state at Co-doping concentration of [Formula: see text]. The absorbance of films increases and the absorption edge shifts to longer wave length direction with increasing Co-doping concentration. The redshift of the band gap energy depends on the Co composition associating with the Urbach energy. Furthermore, the refractive index and dielectric constant increase with increasing Co-doping concentration. The dispersion parameters, such as dispersion energy ([Formula: see text]), oscillator energy ([Formula: see text]), static refractive index ([Formula: see text]), static dielectric constant ([Formula: see text]), interband transition strength moments ([Formula: see text] and [Formula: see text]), oscillator strength [Formula: see text] and oscillator wavelength [Formula: see text], have been analyzed by Wemple–DiDomenico single oscillator model. All these parameters were found to be dependent upon the Co-doping concentration in the Zn[Formula: see text]CoxS thin films.

From core–shell particles to dense Ba0.8Sr0.2Zr0.1Ti0.9O3@Bi2O3–Fe2O3–SiO2 ceramics with low sintering temperature and improved dielectric, energy storage properties

To achieve high energy storage in dielectric ceramics, a new designed material Ba0.8Sr0.2Zr0.1Ti0.9O3@Bi2O3–Fe2O3–SiO2 with core–shell structure was fabricated by the monodispersed submicron Ba0.8Sr0.2Zr0.1Ti0.9O3 particles (diameter ~ 180 nm) coated with the 25-nm-thick shell of Bi2O3–Fe2O3–SiO2. The influences of Bi2O3–Fe2O3–SiO2 amount, Bi/Fe ratio, and sintering temperature on the phase composition, microstructure, and ceramic electrical properties were investigated. X-ray diffraction analysis of the ceramics revealed the formation of perovskite Ba0.8Sr0.2Zr0.1Ti0.9O3 when the Bi2O3–Fe2O3–SiO2 amount was below 6.0 wt%. The secondary phases Bi2Fe4O9 and Bi4Ti3O12 formed in ceramics when the Bi2O3–Fe2O3–SiO2 amount exceeded 6.0 wt%, as the ceramic grain core–shell structure collapsed. Based on FESEM images, the densification of ceramics can be tenderly controlled at low sintering temperature, and the ceramic grains can maintain their core–shell structure. As the Bi2O3–Fe2O3–SiO2 amount, the ratio of Bi to Fe, and the sintering temperature increase, the ceramic room temperature dielectric constant increases up to a maximum value then decreases. The energy storage density exhibits a similar tendency to increase first and then decrease. Fine-grained Ba0.8Sr0.2Zr0.1Ti0.9O3@Bi2O3–Fe2O3–SiO2 ceramics with Bi/Fe ratio of 1.04 and 6.0 wt% Bi2O3–Fe2O3–SiO2 sintered at 1120 °C had a dielectric constant of 2599, the maximum energy storage density of 1.50 J/cm3 under 29.31 kV/mm. This work proposed a novel method to enhance electrical properties of functional materials, which could be potentially used in the fabrication of capacitors with high energy storage performance.

Enhanced dielectric properties of sandwich‐structured biaxially oriented polypropylene by grafting hyper‐branched aromatic polyamide as surface layers

AbstractThis work represents multilayer films with sandwich structure by grafting hyper‐branched aromatic polyamide (HBP) on both sides of biaxially oriented polypropylene (BOPP) (HBPBOPPHBP). BOPP serves as the middle layer to offer high breakdown strength and HBP acts as surface layers to boost the dielectric constant. As a result, the dielectric constant increases significantly from 2.2 of control BOPP to 5.5 (almost increased 1.5 times) after grafting 2.06 μm HBP surface layers, while the dielectric loss still remains at a very low level (<0.03). In addition, all HBPBOPPHBP sandwich‐structured films show higher charge energy density than that of unmodified BOPP. For instance, the discharge energy density of HBPBOPPHBP (1‐20‐1) film is up to 2.38 J/cm3 at an applied electric field of 400 kV/mm, which increases about 36% over that of pure BOPP (i.e., 1.75 J/cm3). Meanwhile, charge–discharge efficiency retains about 90%. This work offers a simple strategy to fabricate polymer‐based high performance dielectric composites.

Preparation and spectroscopic studies of PbI2-doped poly(methyl methacrylate) nanocomposites films: Dielectric and optical limiting approach

In this work, a solution casting method was used to prepare the PbI2/PMMA nanocomposites films. XRD was used to achieve structural characterizations. An increase in an amorphous hump was showed after doping with PbI2 nanostructured. The spectra of FTIR were evaluated between (4000–400 cm−1). The carbonyl stretch band at 1754 cm−1 shifted to higher wavenumber shows the electrostatic interaction between PbI2 and the oxygen of the carbonyl group. Nanocomposites films were identified by scanning electron microscope. The optical UV–Vis–NIR aspects of the nanocomposite films were determined. Increasing the concentration of PbI2 in the investigated samples caused the energy gap to be decreased. Such adjustments in the optical characteristics of the PMMA sample are because of the interaction between the PMMA matrix and the PbI2 nanoparticles. AC electrical conductivity and dielectric properties were studied at room temperature. The dielectric constant increases with increasing the concentration of PbI2. Optical limiting was evaluated and investigated for PbI2/PMMA nanocomposites and the He–Ne and green lasers power was reduced by increasing PbI2 contents. The PbI2/PMMA nanocomposites are promising candidates for solar cells, electronic/optoelectronic devices, and CUT-OFF laser filters.

CdSe nanorod-reinforced poly(thiophene) composites in designing energy storage devices: study of morphology and dielectric behavior

The present study reports the findings about developing the energy storage resources following a green and economically viable method. Polythiophene (PTh) and its nanocomposites (PTh/CdSe) were synthesized using a chemical oxidative polymerization method. The FTIR spectra of the as-prepared composite confirm the presence of CdSe in PTh matrix. The XRD spectra suggest for the amorphous nature of native PTh which further changes into semicrystalline nature when CdSe was incorporated into it. PTh/CdSe nanocomposites showed both cubic and hexagonal phases, and the crystallite size was found to increase from 8 nm to 45 nm when CdSe was reinforced into the PTh matrix. Transmission electron microscopic images of pure PTh showed spherical morphology of the particles joined to each other through van der Waals forces. The doping of CdSe also results in appearance of needle-like nanostructures over PTh surfaces. These isolated needles have CdSe nanorod-like structures. Impedance data reveal that charge transfer resistance (Rct) of pure PTh is higher than that of the PTh/CdSe nanocomposites. The reduced charge transfer resistance (Rct) indicates that conductivity of nanocomposites is higher than that of the native one. When PTh was reinforced with the CdSe, they showed an increase in dielectric constant which is due to the alignment of polarization charges with increased frequency. This mechanism of polarization is helpful in increasing the charge storage capacity of the material. Thus, the observed results may open up doors of new avenues to design energy storage devices using conducting polymer/semiconductor nanocomposites.

Influence of IrO2 addition on magnetoelectric properties of Ni0.5Zn0.5Fe2O4/Ba0.8Sr0.2TiO3 composite ceramics

Ni0.5Zn0.5Fe2O4/Ba0.8Sr0.2TiO3 (NZFO/BST) magnetoelectric composites were synthesized through traditional solid-phase method, and effects of IrO2 addition on the microstructure, surface appearance and magnetoelectric properties were comparatively investigated. XRD patterns demonstrate a spinel structure of NZFO and tetragonal perovskite structure of BST, and the addition of IrO2 is conducive to improving the crystallinity of materials. SEM presents that a certain amount of IrO2 is beneficial to the growth of ceramic grains and the densification of ceramics. Through SEM and EDS analysis, it is found that the smaller grain size is BST, and its size is about 100 nm. Sample NZFO/BST-5% has the largest average grain size (~ 277.51), while sample NZFO/BST-1% has a relative density of 91.23%. The relaxation behavior is more obvious with the addition of a certain content of IrO2, which leads to the increase of dielectric constants. In the high temperature region (> 200 ℃), the sample exhibits a large dielectric loss, particularly, the more the content of IrO2, the more obvious this phenomenon is. The addition of IrO2 causes the larger leakage current of NZFO/BST composites so that samples NZFO/BST-3% and NZFO/BST-5% exhibit poor ferroelectricity, in addition, the magnetic properties of the sample are also weakened, and the NZFO/BST composites exhibited a soft ferromagnetic behavior.

Dielectric modulated transparent gate thin film transistor for biosensing applications

This work presents a transparent gated thin film transistor (TGTFT) for biosensing purpose, having a small cavity for biomolecules detection and also the transparent of TG-TFT enriches the current effectiveness of TG-TFT. Various electrical properties like switching ratio (ION/IOFF), VTH shifts, and potential fluctuations have been examined for biomolecule sensing and then sensitivity was examined. TG-TFT Biosensor presented an incremental sensitivity for an increase in dielectric constant (k) value because of the high ION. Sensitivity was evaluated with comparison to k = 1 (i.e. air) and formula for the same is discussed later. Some other electrical properties such as electric field, potential, and mobility are also discussed and compared with other biomolecules.

Structural and electrical investigations of pure and rare earth (Er and Pr)-doped NiO nanoparticles

Applying the coprecipitation technique, we synthesized PVA-capped Ni0.98RE0.02O (RE = Er md Pr) nanoparticles. Thermogravimetric analysis (TGA) was performed to study the thermal stability of the prepared samples to choose the calcination temperature accordingly. Thermal stability was attained at ~ 823 K with no further thermal decomposition beyond. The crystallinity and phase formation of the prepared samples were confirmed by powder X-ray diffraction XRD. Studying the effect of RE3+ doping on the structural parameters of NiO nanoparticles was facilitated by X-ray peak profile analysis, based on the Debye Scherer model, Williamson–Hall model and size strain plot. The doped samples exhibited smaller lattice parameter and strain, with the minimum strain along the (200) direction. Also, a smaller crystallite size was found for the doped samples, depending on the dopant’s ionic radius, giving rise to higher dislocation density and specific surface area. Transmission electron microscopy (TEM) proved the nanoscale of the prepared samples, in agreement with the XRD outcomes, and revealed slight agglomeration of homogeneous nanoparticles. DC conductivity indicated the semiconducting behavior of the prepared samples, triggered by Ni2+ vacancies. Hopping mechanism was found to be the conduction process with two activation energies, depending on the temperature range of study. The dielectric behavior was explained by Maxwell–Wagner interfacial polarization, in agreement with Koop’s theory. The correlated barrier hopping mechanism CBH was found to be the conduction mechanism. Moreover, the Nyquist plot was investigated. Doping by rare earth elements resulted in an increase in dielectric constant, AC and DC conductivities.

Dielectric properties of micro-composites based on acrylic coated conducting carbon particles and silicone elastomer

The present embodiment provides an insight on the fabrication and characterization of polymeric dielectric compositesfor energy storage applications required in mobile electronic devices, stationary power systems, hybrid electric vehicles andpulse power generation. In present study, conducting carbon particles of appropriate dielectric properties have beenselectively functionalized with acrylic resin using micro-ballooning method to form core shell conducting particles in orderto tailor its conductivity and dielectric properties (dielectric loss in particular). The core shell conducting particles were thenmixed with silicone resin in varied proportions (10, 20, 25 and 30 % wt/wt) to form flexible dielectric micro-compositeswhich exemplify concomitant increase in dielectric constant without impairing dielectric loss owing to selective coating ofcarbon particles via micro-ballooning method. Formulation containing 25wt% core shell conducting particles showed mostlinear variation in dielectric constant and dielectric loss factor (tan ) with respect to frequency due to feeble contribution ofinterfacial polarization.

Investigation on behavioural aspects of pine apple leaf fiber–latex composites used for transformer applications

The transformers perform the task of transmitting power to the power systems. The reliability of the power transformers decreases and the risk of failure increases due to the increasing operational time. The overall life of transformers that depends on the life of oil-paper insulation system throughout its operation. In most cases they fail due to the poor performance of the insulation paper. At the present time, technology is used to manufacture materials from agricultural waste which considered as a substitute to natural wood, due to the problem of global warming. The ever-increasing demand of the biodegradable polymer composites and natural fibers have great importance over synthetic fibers because of vast availability in nature. The natural rubber (Latex) remains attractive for several applications due to its low temperature flexibility, high elasticity, fatigue resistance, tearing resistance and low temperature build up.The objective of the study is to investigate the Thermal, Dielectric and Physical properties of pine apple leaf fiber (PALF) reinforced natural rubber composites. The samples of different volume fractions of the fiber typically (5%, 10%, 15%, 20%, 25%, 30%) have been selected. It is found that the Thermal, Dielectric and Physical properties were influenced by fiber volume fraction. The Dielectric constant increases and Thermal conductivity decreases with increasing of fiber content.

Electrical conductivity and dielectric properties of solid polymer nanocomposite films: Effect of BaTiO3 nanofiller

Polymer nanocomposite comprising of PEO-PVC + LiClO4 with BaTiO3 as nanofiller were synthesized by the solution cast technique. The dispersion of the nanofiller in the polymer matrix promotes fast ion migration. Impedance study reveals that the ionic conductivity is enhanced by the addition of BaTiO3 and the maximum value is 2.35 × 10−5 S cm−1 for 3 wt. % BaTiO3 attributed to favorable conductive path formation for cation. The ion transference number is close to unity and the voltage stability window is of the order of 3.5 V. The complex dielectric permittivity, dielectric loss, complex conductivity, was studied and fitted with the corresponding established expression in the entire frequency range (1–100 kHz). The dielectric constant increases with the addition of the nanofiller and is attributed to the complete salt dissociation. The ac conductivity analysis displays a shift of dispersion region toward high frequency which is attributed to the faster ion migration and also evidenced by lowering of relaxation time. It has been noticed that the relevant parameters like ionic conductivity, ion transference number, voltage stability and the dielectric parameters are dependent on the content of nano-sized BaTiO3 filler content. A systematic ion transport mechanism has been proposed to highlight the role of nanofiller in enhancing the desired parameters.

Direct writing of PVDF piezoelectric film based on near electric field added by [Emim]BF4

PVDF/IL piezoelectric film based on [Emim]BF4-added was prepared by near electric field direct writing. The β-phase content and its electric property of the film were analyzed. The results showed that the content of β crystal phase of PVDF film was improved by the synergistic effect of IL ([Emim]BF4) and near electric field. When the amount of [Emim]BF4 added was 1.5 wt%, the relative β-phase content of PVDF film reached 85.09%, and the crystallinity is 47.84%. Increase in [Emim]BF4 content resulted in a significant increase in the relative dielectric constant of the film, from 6 to 285, but also accompanied by a sharp increase in dielectric loss. The d33 value of the film can be as high as −10 pC/N, and the output voltage from the cantilever beam vibration feedback indicates that the voltage strength of the [Emim]BF4-added film is greatly improved compared with the pure PVDF film.