Application Of Electric Field Research Articles

First-principles study on the effects of fast neutron irradiation and fast neutron irradiation under the external electric field on carbon-based material AB bilayer graphene

The irradiation damage mechanism of fast neutron irradiation and the fast neutron irradiation under the practical application of an additional electric field on carbon-based material AB bilayer graphene is not yet clear. This paper systematically investigates the impact of fast neutron irradiation and fast neutron irradiation under the practical application of the additional electric field (−0.2 V/Å) on carbon-based material AB bilayer graphene through density functional theory and molecular dynamics simulations. The research results indicate that the changes in the configuration of AB bilayer graphene and the appearance of surface ripples induced by fast neutron irradiation are the two main reasons for the alterations in the system's microstructure, band structure, Young's modulus, and optical properties, which may lead to performance degradation and damage of carbon-based devices. The further variation in the average interlayer spacing of the system under external electric field irradiation leads to the diversity of the system configuration, which ultimately leads to the diversity of the band structure of the system. The uncertainty in the type and width of the bandgap in AB bilayer graphene under fast neutron irradiation with an external electric field may be one of the reasons for the performance degradation and permanent damage of carbon based devices in practical applications. In the fast neutron irradiation environment, the precise control of the bandgap of AB bilayer graphene by an applied electric field will fail.

Applied electric field to repair metal defects and accelerate dehydrogenation

Repairing metal micro-defects at the atomic level is very challenging due to their random dispersion and difficulty in identification. At the same time, the interaction of hydrogen with metal may cause hydrogen damage or embrittlement, endangering structural safety. As a result, it is critical to speed up the dehydrogenation of hydrogen-containing materials. The applied electric field can repair the vacancy defects of the material and accelerate the dehydrogenation of the hydrogen-containing metal. The influence of the external environment on the diffusion coefficient of hydrogen in polycrystalline metals was researched using molecular dynamics in this article, and the mechanism of hydrogen diffusion was investigated. Simultaneously, the mechanical characteristics of Fe3Cr alloy were compared during typical heat treatment and electrical treatment. The effect of temperature, electric field strength, and electric field direction on the diffusion coefficient was investigated using orthogonal test analysis. The results demonstrate that temperature and electric field strength have a significant impact on the diffusion coefficient. The atom vibrates violently as the temperature rises, breaking past the diffusion barrier and completing the atomic transition. The addition of the electric field adds extra free energy, decreases the atom’s activation energy, and ultimately enhances the atom’s diffusion coefficient. The repair impact of vacancy defects under electrical treatment is superior to that of typical annealing treatment for polycrystalline Fe3Cr alloy. The electric field can cause the dislocation to migrate, increasing the metal’s toughness and plasticity. This research serves as a useful reference for the electrical treatment of metal materials and offers a method for the quick dehydrogenation of hydrogen-containing materials.

Can rare earth elements be recovered from abandoned mine tailings by means of electrokinetic-assisted phytoextraction?

Given the high impact of traditional mining, the recovery of rare earth elements (REEs) from hazardous waste materials could become an option for the future in accordance with the principles of the circular economy. In this work, the technical feasibility of REEs recovery from metal mine tailings has been explored using electrokinetic-assisted phytoremediation with ryegrass (Lolium perenne L.). Phytoextraction combined with both AC current and DC current with reversal polarity was applied (1 V cm−1, 8 h day−1) to real mine tailings containing a total concentration of REEs (Sc, Y, La, Ce, Pr, and Nd) of around 146 mg kg−1. Changes in REEs geochemical fractionation and their concentrations in the soil pore water showed the mobilization of REEs caused by plants and electric current; REE availability was increased to a higher extent for combined electrokinetic-assisted phytoextraction treatments showing the relevant role of plants in the process. Our results demonstrated the initial hypothesis that it is feasible to recover REEs from real metal mining waste by phytoextraction and that the performance of this technology can be significantly improved by applying electric current, especially of the AC type, which increased REE accumulation in ryegrass in the range 57–68% as compared to that of the treatment without electric field application.

Superior nanocomposites of phosphonium-based poly(ionic liquid) with halloysite and graphene oxide: Electrorheological investigations

Phosphonium-based poly(ionic liquid) (PPIL) as well as its nanocomposites with halloysite (HNT) and graphene oxide (GO) were synthesized in this study. PPIL structure was engineered to be poly[(4-vinylbenzyl) trimethyl phosphonium trifluoromethane sulfonate] for high electrorheological (ER) performance. To improve ER properties of PPIL, HNT clay with strong mechanical, thermal, and insulating properties and GO with strong dielectric properties were introduced into the PPIL structure by covalent bonding. The synergistic electroactive effect of HNT and GO in the hybrid nanocomposites were investigated by comparing PPIL, HNT/PPIL and HNT/GO/PPIL structures. Structural, thermal, and morphological characterizations approved the successful synthesis of samples. Dielectric and ER flow tests of dispersions of the engineered structures in insulating silicone oil (SO) indicated that PPIL (Δε′ = 1.80 and τy = 250 Pa, EReff = 35, G′ = 33 kPa at 2.0 kV mm-1) and HNT/PPIL (Δε′ = 1.55 and τy = 260 Pa, EReff = 51, G′ = 100 kPa at 2.0 kV mm-1) have similar electroactive properties whereas the highest polarizability and ER response are achieved with HNT/GO/PPIL hybrid nanocomposite (Δε′ = 2.50 and τy = 410 Pa, EReff = 67, G′ = 790 kPa at 2.0 kV mm-1). The findings indicated that electrical stability and electric field induced polarizability of PPIL have been improved by the presence of HNT and GO, respectively. When compared with the previously reported ER studies for ammonium-based poly(ionic liquid)s, PPIL and its nanocomposites of HNT/PPIL and HNT/GO/PPIL exhibited better ER properties, as projected. The application of electric field resulted in the switchable viscoelastic character for PPIL/SO, HNT/PPIL/SO and HNT/GO/PPIL/SO dispersions. Similar to the ER flow properties, the best electroactive viscoelastic properties were obtained for the dispersion of triple HNT/GO/PPIL hybrid nanocomposite. Overall, new ER dispersions of phosphonium-based poly(ionic liquid) and its superior nanocomposites were introduced to the literature.

Accelerating wound healing with flexible zinc ion microbatteries coupled with endogenous electrical fields

Wound healing is an important physiological process in living organisms, involving the migration and proliferation of cells in the endogenous electric field (EEF). Continuous and stable electrical stimulation by an external power supply can effectively mimic the EEF, accelerating the biological processes involved in wound healing. However, the clumsiness of conventional external power supplies and the unstable voltage output of novel power supplies greatly limit the application of electric fields for wound healing. Here we demonstrate the use of a flexible and wearable microbattery for wound healing. The annular electrode is designed to generate an annular electric field in the same direction as the EEF of the wound, allowing for faster, more uniform fibroblast migration, proliferation, and transdifferentiation processes, thus accelerating wound healing. Studies on rats show that skin wounds given a stable electric field using aqueous Zn-MnO2 microbatteries with an operating voltage of 1.5 V healed completely within 6 days, while the blank control group took 10 days or longer. Further, the series connection of microbatteries can match wounds of different areas, enabling rapid healing. These advantages make flexible microbatteries highly promising for practical applications in the biomedical field.

Green Synthesis of Magnetite Nanoparticles Using <i>Moringa oleifera</i> and their Electro-Optic Surface Plasmon Resonance Properties

The application of an external electric field to the surface plasmon resonance (SPR) system of green-synthesized magnetite (Fe3O4) nanoparticles (MNPs) is very promising for increasing the SPR detection signal. Electro-optic surface plasmon resonance (EOSPR) behavior of MNPs has been successfully carried out. The EOSPR system was investigated using the Kretschmann configuration with the prism/Au thin film/MNPs/air layer arrangement and applying an electric voltage of 0 V, 2 V, 4 V, and 6 V. In this study, we synthesized MNPs using the green synthesis approach from moringa oleifera extract. The benefits of green synthesis include being safe, affordable, clean, and ecologically friendly processes. X-ray diffraction results obtained crystal size of the MNPs is about 9.2 nm with inverse spinel face-centered cubic crystal structure. Fourier transforms infrared characterization showed the presence of Fe-O bonds at wave numbers 569 cm-1 and 629 cm-1, indicating that MNPs were successfully formed. The saturation magnetization of the samples is 55.3 emu/g. The SPR angle of the SPR system Prism/Au thin film/air without the addition of MNPs is 44.66°. After being deposited by MNPs and induced by a voltage of 0 V, 2 V, 4 V, and 6 V, the SPR angles changed to 44.87°, 44.90°, 44.95° and 45.12°. The addition of MNPs and an external electric field causes the SPR angle to increase. The results of this study can provide new insights into the development of optical devices that can be manipulated electrically and have the potential for future biosensor applications.

PbBi2Se4 monolayer: A new 2D material with outstanding electronic, photocatalytic, and optical properties

Two-dimensional layered PbBi2Se4 nanosheets were recently successfully produced [Chatterjee et al., Phys. Chem. Chem. Phys., 2014,16, 14,635–14639]. Inspired by these promising experimental findings, herein we examine the electronic and photocatalytic properties of the PbBi2Se4 monolayer by density functional calculations. The phonon dispersion of the designed monolayer validated that the PbBi2Se4 is dynamically and thermally stable. Our results showed that the PbBi2Se4 has a bandgap of 1.211/1.650 eV according to the PBE/HSE06 hybrid functional. In addition, the optoelectronic properties are altered by the application of electric field and strain, but the band gap is more significantly modified by strain than by electric field, which reduces the energy gap. Interestingly, the results of photocatalytic properties revealed that PbBi2Se4 is an effective photocatalyst for hydrogen production. Under the application of a biaxial strain of −8%, the superior absorption coefficient of PbBi2Se4 is 20.1×104cm−1, consequently, the application of strain resulted in an improvement in the absorption of light in the visible and ultraviolet ranges. Furthermore, the greatest value of the conductivity is due to the compressive strain, which is about 8.14×1015 at 3.23 eV for −8%. These results suggest that the PbBi2Se4 monolayer has potential uses in the development of sensors, solar cells, and photocatalysts.

Domain engineered lead-free Bi0.5Na0.5TiO3-Bi(Ni0.5Hf0.5)O3 relaxor ferroelectric ceramics for energy storage with low electric field applications

Lead-free materials for energy storage are increasingly receiving attention due to their exceptional properties of high charging and discharging rates, high power density, and eco-friendliness. In this work, (1−x)Bi0.5Na0.5TiO3-xBi(Ni0.5Hf0.5)O3 (BNT-BNH, x = 0.05, 0.10, 0.15 and 0.20) ceramics were prepared for electrostatic energy storage. P-E loops results show that the introduction of Ni2+ and Hf4+ induces the formation of polar nanoregions (PNRs) and the phase transition from ferroelectric to relaxor ferroelectric in BNT ceramics. Transmission Electron Microscopy directly confirm the increase of crystal plane spacing implies a good solid solution of BNT-BNH, and the number of spherical PNRs increases significantly with increasing the BNH content. Herein, a recoverable energy storage density of 2.68 J/cm3 and relative efficiency of 72.1 % are achieved for 0.8BNT-0.2BNH ceramics under 210 kV/cm. The 0.8BNT-0.2BNH ceramics also exhibit a fast discharge rate (t0.9 = 76 ns), high current density (403.1 A/cm2), and high power density (12.85 MW/cm3), which illustrates that BNT-BNH material systems have good application potential in electrostatic energy storage.

Continuous preparation of carbon nanotube fiber and its potential applications in electrical, thermal, mechanical and biosensing fields

Continuous preparation of carbon nanotube fiber and its potential applications in electrical, thermal, mechanical and biosensing fields

Optimization of Pulsed Electric Field-Based Extraction of Bioactive Compounds from Cannabis sativa Leaves

The current investigation examines the application of pulsed electric fields (PEFs) for isolating polyphenols from Cannabis sativa var. Futura 75 leaves. Firstly, the solvent composition, which included ethanol, water, and various mixtures of the two, was explored, along with the liquid-to-solid ratio. Subsequently, the primary parameters associated with PEFs (namely, pulse duration, pulse period, electric field intensity, and treatment duration) were optimized. The extracted samples were analyzed to determine their total polyphenol content (TPC), and individual polyphenols were also evaluated through high-performance liquid chromatography. In addition, the antioxidant activity of the extracts was assessed through ferric-reducing antioxidant power (FRAP) and DPPH assays. The extracts prepared utilizing PEFs were compared to the extracts obtained without PEFs in terms of their TPC, FRAP values, and DPPH activity. The results indicate that the most effective extraction parameters were a pulse duration of 10 μs, a pulse period of 1000 μs, and an electric field strength of 0.9 kV/cm after 25 min of extraction. The most efficient solvent was determined to be a 50% (v/v) mixture of ethanol and water in a 20:1 liquid-to-solid ratio. The extract obtained under the optimal conditions exhibited a ~75% increase in TPC compared to the extract obtained without any application of PEFs, while some individual polyphenols exhibited an increase of up to ~300%. Furthermore, significant increases of ~74% and ~71% were observed in FRAP and DPPH assays. From the information provided, it was observed that the tested variables had an impact on the recovery of polyphenols from C. sativa leaves.

Composition-driven phase coexistence and functional properties of the (1-x)BZT-(x)BCT ceramics near the phase convergence region

The concept of composition-induced phase transformation in Lead Zirconate Titanate (PZT) at the Morphotropic Phase Boundary (MPB) has been employed to improve functional properties of the (1-x)BZT-(x)BCT ceramic. However, it was observed that the phase diagram of the (1-x)BZT-(x)BCT ceramic is different to the PZT. As a result, the nature of the superior functional properties found in (1-x)BZT-(x)BCT ceramic is unlike PZT and still unclear so far. In this work, functional properties; dielectric, ferroelectric, energy storage, and piezoelectric properties, of the (1-x)BZT-(x)BCT ceramics where x = 0.3 mol% to 0.6 mol% were evaluated at room temperature in comparison to the identification of phase coexistence using synchrotron x-ray powder diffraction (SXPD). This work found that changes of BCT content had a strong impact on the observed coexisting phases and functional properties. Moreover, the composition that showed the highest piezoelectric properties did not present the largest of saturation polarization. This implies that the functional properties of the (1-x)BZT-(x)BCT ceramics are not dependent on the presence of polarizations under the application of electric field. The contribution of non-180° domain switching also plays a vital role, especially in the piezoelectric properties. These findings would help to extend our knowledge of the nature of the (1-x)BZT-(x)BCT ceramic.

My Vision of Electric-Field-Aided Chemistry in 2050.

This manuscript outlines my outlook on the development of electric-field (EF)-mediated-chemistry and the vision of its state by 2050. I discuss applications of oriented-external electric-fields (OEEFs) on chemical reactions and proceed with relevant experimental verifications. Subsequently, the Perspective outlines other ways of generating EFs, e.g., by use of pH-switchable charges, ionic additives, water droplets, and so on. A special section summarizes conceptual principles for understanding and predicting OEEF effects, e.g., the "reaction-axis rule", the capability of OEEFs to act as tweezers that orient reactants and accelerate their reaction, etc. Finally, I discuss applications of OEEFs in continuous-flow setups, which may, in principle, scale-up to molar concentrations. The Perspective ends with the vision that by 2050, OEEF usage will change chemical education, if not also the art of making new molecules.

Bioelectrochemically enhanced biomethane production from low-rank coal using multiple microbial strains

Although microbial in-situ gasification of coal has been established to be an environmentally friendly and sustainable mining method, the low efficiency of methane production via coal micro-gasification limits the commercial applicability of this technology. In this regard, the application of electric fields can contribute to enhancing the efficiency of anaerobic microbial coal degradation. In this study, to investigate the effects of low-intensity electric fields on coal degradation by different exogenous microbial species, we conducted laboratory-scale batch anaerobic fermentation experiments at 0.9, 1.5, and 2.2 V using a micro-gas measuring device to quantify biogas production. The results revealed that application of a low-intensity electric field can promote the production of methane by different microbes, with the highest gas production (7.92 mL/g) obtained at 1.5 V, representing an increase of 131.58 % compared with fermentation conducted in the absence of an applied electric field. The electrodes facilitated the microbial utilization or dissolution of organic matter on the coal surface, leading to a reduction in surface functional groups, with the fermentation medium mainly comprising aromatic hydrocarbons. The coal particles at the anode appeared rough. Collectively, our findings in this study revealed that the application of electric fields contributed to a modification of microbial metabolism and promoted an enhancement of methane production. We believe these findings have important implications for enhancing the microbial production of biomethane from coal.

Analyzing photoionization cross-sectional modulation in CdSe/CdS core–shell nanodots: Impact of strain and applied electric field

The role of strain in material properties is well-established, serving as a tool for altering atomic positions and defect formation, adjusting electronic structures and lattice vibrations, and influencing phase transitions, physical characteristics, and chemical properties. In this study, we conducted theoretical calculations of the binding energy and photoionization cross section (PCS) within a spherical core/shell quantum dot (CSQD) for the different transitions between the ground state of a donor impurity and the four low-lying conduction band states. During our study, we employed the finite element method to determine the energy levels and wave functions of the system within the effective mass approximation. Subsequently, we investigated the changes in PCS and binding energy while varying shell width under the influence of an applied electric field, considering both cases with and without the effect of strain. The strain effect was incorporated based on Hooke's law, and we developed specific expressions and utilized the continuum linear elasticity mechanical model for a single spherically symmetric shell. The results demonstrate that the strain correction enhances the binding energy of the four low-lying energy levels, leading to a shift of the PCS peaks toward higher energies. Conversely, the application of an external electric field has varying effects depending on the specific transition being considered. We compared our theoretical results with available experimental data and found them to be in good agreement. The pronounced blue-shift and substantial enhancement in magnitude of PCS spectra concerning shell width, electric field, and strain make CSQDs highly promising candidates for applications in adjustable nano-optoelectronic devices.

Probing Electronic Band Structures of Dielectric Polymers via Pre-Breakdown Conduction.

The electronic band structure, especially the defect states at the conduction band tail, dominates electron transport and electrical degradation of a dielectric material under an extremely high electric field. However, the electronic band structure in a dielectric is barely well studied due to experimental challenges in detecting the electrical conduction to an extremely high electric field, i.e., prebreakdown. In this work, the electronic band structure of polymer dielectric films is probed through an in situ prebreakdown conduction measurement method in conjunction with a space-charge-limited-current spectroscopic analysis. An exponential distribution of defect states at the conduction band tail with varying trap levels is observed in accordance with the specific morphological disorder in the polymer dielectric, and the experimental defect states show also a favorable agreement with the calculated density of states from the density functional theory. The methodology demonstrated in this work bridges the molecule-structure-determined electronic band structure and the macro electrical conduction behavior with a highly improved understanding of material properties that control the electrical breakdown, and paves a way for guiding the modification of existing material and the exploration of novel materials for high electric field applications.

Droplet Motion Driven by Liquid Dielectrophoresis in the Low-Frequency Range.

Electrohydrodynamic wetting manipulation plays a major role in modern microfluidic technologies such as lab-on-a-chip applications and digital microfluidics. Liquid dielectrophoresis (LDEP) is a common driving mechanism, which induces hydrodynamic motion in liquids by the application of nonhomogeneous electrical fields. Among strategies to analyze droplet movement, systematic research on the influence of different frequencies under AC voltage is missing. In this paper, we therefore present a first study covering the motion characteristics of LDEP-driven droplets of the dielectric liquids ethylene glycol and glycerol carbonate in the driving voltage frequency range from 50 Hz to 1600 Hz. A correlation between the switching speed of LDEP-actuated droplets in a planar electrode configuration and the frequency of the applied voltage is shown. Hereby, motion times of different-sized droplets could be reduced by up to a factor of 5.3. A possible excitation of the droplets within their range of eigenfrequencies is investigated using numerical calculations. The featured fluidic device is designed using larger-sized electrodes rather than typical finger or strip electrodes, which are commonly employed in LDEP devices. The influence of the electrode shape is considered simulatively by studying the electric field gradients.

Study of the behavior of polyvinylidene fluoride (PVDF) under the action of electric field using semi-empirical methods (PM3)

Piezoelectric material has the property of converting energy from the mechanical pressure of an external body into electrical energy on the piezo-structure, providing a strong potential source for renewable energy. Our aim in this article is to explore the properties of polyvinylidene fluoride polymer under the influence of an electric field. In sense to understand the behavior of integer polymer, we started to simulate the optimization of several small sizes (monomer, dimmer, trimer and tetramer) of this polymers subjected to uniform electric fields in the direction of the electric dipole applying a external electric field and analyzing the displacement of electrical charges. For this optimization of this polymer we used PM3 semi-empirical methods applying electric field applications. These results elucidate the behavior of electrical charges of an organic piezoelectric material under the action of external and uniform electric field.

Van der Waals heterostructures of AlAs and InSe: Stacking-dependent Raman spectra and electric field dependence of electronic properties

In the present work, the electronic and vibrational properties of a van der Waals type heterostructure, composed of single layers of AlAs and InSe, are investigated using density functional theory (DFT)-based first-principles calculations. Vibrational analyses reveal that dynamically stable single layers of AlAs and InSe form van der Waals type heterostructure which is shown to exhibit stacking-dependent Raman spectra by means of the frequency shifts. According to our findings, a type-II band alignment with a direct band gap of 1.84 eV is found in the ground state stacking of AlAs/InSe vertical heterostructure, in contrast to the indirect band gap behaviors of each individual layer. Moreover, the application of an external vertical electric field shows that the both band alignment type and the electronic behavior of the heterostructure can be tuned. The heterostructure is found to exhibit direct to indirect band gap transition under negative electric field as well as a transition from type-II to type-I heterojunction under negative fields up to 0.3 V/Å. The stronger fields along the same direction results in overlapping of valence states of each layer and lead to a non-linear change of the energy band gap. Overall, the predicted van der Waals type heterobilayer of InSe and AlAs with stacking-dependent vibrational features and well-controlled electronic properties under external field is shown to be potential candidate for optical and optoelectronic applications.

Effect of electric field on the structure of SiCN pyrolyzed at 1600 °C

Application of electric field is known to influence the phase transformation and sintering conditions of ceramics. In this work, the effect of electric field on the phase structure evolution of SiCN pyrolyzed at 1600 °C was studied in comparison with conventional pressureless pyrolyzed SiCN. The structural information was characterized via X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and Raman spectroscopy. It was found that SiCN ceramic prepared via conventional pressureless pyrolysis was composed of SiC, Si3N4 and free carbon phases, while that produced via electric field-assisted pyrolysis consisted of Si3N4 and free carbon phases. No crystalline SiC was detected in SiCN ceramic pyrolyzed via the field-assisted method, indicating that the electric field affected the carbothermal reaction between Si3N4 and C phases and changed the formation mechanism of SiC. Moreover, the electric field promoted structural ordering rearrangement of the free carbon phase and increased the defect content therein.

Evaluating the Effects of Pulsed Electrical Stimulation on the Mechanical Behavior and Microstructure of Medulla Oblongata Tissues.

The development of remote surgery hinges on comprehending the mechanical properties of the tissue at the surgical site. Understanding the mechanical behavior of the medulla oblongata tissue is instrumental for precisely determining the remote surgery implementation site. Additionally, exploring this tissue's response under electric fields can inform the creation of electrical stimulation therapy regimens. This could potentially reduce the extent of medulla oblongata tissue damage from mechanical compression. Various types of pulsed electric fields were integrated into a custom-built indentation device for this study. Experimental findings suggested that applying pulsed electric fields amplified the shear modulus of the medulla oblongata tissue. In the electric field, the elasticity and viscosity of the tissue increased. The most significant influence was noted from the low-frequency pulsed electric field, while the burst pulsed electric field had a minimal impact. At the microstructural scale, the application of an electric field led to the concentration of myelin in areas distant from the surface layer in the medulla oblongata, and the orderly structure of proteoglycans became disordered. The alterations observed in the myelin and proteoglycans under an electric field were considered to be the fundamental causes of the changes in the mechanical behavior of the medulla oblongata tissue. Moreover, cell polarization and extracellular matrix cavitation were observed, with transmission electron microscopy results pointing to laminar separation within the myelin at the ultrastructure scale. This study thoroughly explored the impact of electric field application on the mechanical behavior and microstructure of the medulla oblongata tissue, delving into the underlying mechanisms. This investigation delved into the changes and mechanisms in the mechanical behavior and microstructure of medulla oblongata tissue under the influence of electric fields. Furthermore, this study could serve as a reference for the development of electrical stimulation regimens in the central nervous system. The acquired mechanical behavior data could provide valuable baseline information to aid in the evolution of remote surgery techniques involving the medulla oblongata tissue.