Additional Electric Field Research Articles

Magnetorheological characterization of oil-in-oil magnetic Pickering emulsions

A magnetic Pickering emulsion is a type of emulsion stabilized by magnetic nanoparticles that accumulate at the droplet interface. This makes the emulsion easy to control using an external magnetic field, which, in turn, makes it useful in many applications. Research and development in this field are ongoing, but regardless of the application, control of the formation process is necessary. Rheological measurements are one of techniques used for evaluating the internal structure and stability of emulsions. The main focus of the current research is to investigate the magnetorheological effect of the rarely tested oil-in-oil (O/O) magnetic Pickering emulsions and compare them with better-characterized oil-based magnetic fluids.The magnetoviscous effect typically occurs when magnetic nanoparticles or magnetic Pickering emulsions align with the magnetic field, and this effect depends mainly on the internal structure, such as the size and shape of the particles and droplets. The experimental results indicate that the magnetic emulsion fabricated utilizing ultrasound and an additional electric field exhibits higher dynamic yield stress as a function of the magnetic field compared with the partially covered droplets. This suggests that the stable emulsion becomes a more rigid system and is more resistant to deformation when a magnetic field is applied. Besides that, the magnetoviscous effect of the magnetic emulsions was lower compared with that of magnetic suspensions with the same mass fraction of magnetic nanoparticles.

High photoresponsivity MoS2 phototransistor through enhanced hole trapping HfO2 gate dielectric

Phototransistor using 2D semiconductor as the channel material has shown promising potential for high sensitivity photo detection. The high photoresponsivity is often attributed to the photogating effect, where photo excited holes are trapped at the gate dielectric interface that provides additional gate electric field to enhance channel charge carrier density. Gate dielectric material and its deposition processing conditions can have great effect on the interface states. Here, we use HfO2 gate dielectric with proper thermal annealing to demonstrate a high photoresponsivity MoS2 phototransistor. When HfO2 is annealed in H2 atmosphere, the photoresponsivity is enhanced by an order of magnitude as compared with that of a phototransistor using HfO2 without annealing or annealed in Ar atmosphere. The enhancement is attributed to the hole trapping states introduced at HfO2 interface through H2 annealing process, which greatly enhances photogating effect. The phototransistor exhibits a very large photoresponsivity of 1.1 × 107 A W−1 and photogain of 3.3 × 107 under low light illumination intensity. This study provides a processing technique to fabricate highly sensitive phototransistor for low optical power detection.

Optimizing Kinetics for Enhanced Potassium‐Ion Storage in Carbon‐Based Anodes

AbstractThe sluggish kinetics in traditional graphite anode greatly limits its fast‐charging capability, which is critically important for commercialization of potassium ion batteries (PIBs). Hard carbon possesses randomly oriented pseudo‐graphitic crystallites, enabling homogeneous reaction current and superior rate performance. Herein, a series of hybrid anodes with different hard carbon/graphite ratios are prepared by uniformly mixing graphite and hard carbon with ball‐milling. Comprehensive experimental results in combination phase‐field simulations reveal that the hybrid anode possesses a homogeneous reaction current and an intriguing potential difference between K+‐adsorbed hard carbon and non‐potassiated graphite. The homogeneous reaction current in the hybrid anode promotes sufficient utilization of electrode material, leading to an increase in the reversible capacity. The present potential difference between K+‐adsorbed hard carbon and non‐potassiated graphite provides an additional electric field force that facilitates the diffusion of K+ from hard carbon into the nearest neighbor graphite. All these together, emphasize the synergistic effects between hard carbon and graphite in hybrid anodes toward satisfactory rate and cycling performance. The hybrid strategy proposed here is compatible with the commercial battery manufacturing, offering a practical pathway for the development of high‐performance PIBs.

Metal-semiconductor direct-current triboelectric nanogenerator based on depletion mode u-GaN/AlGaN/AlN/GaN HEMT

The urgent need for renewable energy source has led to a significant interest in triboelectric nanogenerators (TENGs) as a new energy technology. In contrast to traditional polymer TENGs, semiconductor direct-current TENGs are more suitable for miniaturization and integration with electronic devices. This study proposes a friction material made of depletion mode GaN high electron mobility transistors (HEMTs), which exhibit superior properties such as high two-dimensional electron gas concentration. By sliding a titanium sheet on a depletion mode GaN-based heterostructure, we have designed a metal-semiconductor direct-current triboelectric nanogenerator that achieved voltage up to 45.5 V and a peak power density of 2.32 W/m2. This generator can be used to supply DC power to 14 LEDs in series and drive a digital watch directly. In particular, the generation of direct current is predominantly influenced by the surface states of the undoped GaN cap that produce a large number of electrons and are associated with an additional electric field in the direction of the two-dimensional electron gas created in the u-GaN/AlGaN/AlN/GaN heterostructure of depletion mode GaN-based HEMTs. This research not only introduces a nitride semiconductor material of GaN-based HEMTs for the metal-semiconductor interface friction in the DC TENGs but also elucidates the current generation mechanism of GaN-based HEMT TENGs.

Photoemission enhancement of InxGa1-xN nanowire array photocathode

The semiconductor material InxGa1-xN can be used in optoelectronic devices to achieve a tunable wide spectral response. Based on “Spicer's model” and “Andachi's model”, a complete theoretical model of photoemission of reflective InxGa1-xN nanowire array photocathode is established. The results show that the photocathode has a sharp cut-off characteristic, and the increase of the nanowire height is conducive to enhancing the quantum efficiency in the response band. Both oblique light and additional electric field can improve the electron collection efficiency of the anode. With an incidence angle of 0° to 40°, the collection efficiency of photocathodes with H = 800 nm is improved, with a maximum increase of 50.21%. In addition, the electron collection efficiency of nanowire photocathode with H = 400 nm, β = 20°and Eout = 0.4 V/μm can be enhanced by 121% compared to the traditional planar photocathode. This work is expected to provide theoretical guidance for researching the InGaN photocathode electron source.

A Quantum-mechanical Treatment of Electron Broadening in Strong Magnetic Fields

Spectral line-shape fitting is an extremely useful tool in determining the gravity of white dwarf stars. This method is so far limited to nonmagnetic white dwarfs largely because the theory of line broadening in high magnetic fields is not as complete as in the nonmagnetic case. Current Stark+Zeeman models treat plasma particles classically and ignore the motion of the nucleus. We develop the formalism for a quantum-mechanical treatment of the perturbing electrons and include the nuclear motion as part of the broadening and explore their relative importance. The conditions we explore are those found in white dwarf and neutron star atmospheres. We find that, contrary to previous studies, the quantized perturbing electrons create more broadening than perturbers on a straight-path trajectory. Additionally, the quantization of the plasma electrons gives rise to resonances away from the line center. The nuclear motion creates an additional electric field, which also leads to an increase in line broadening; however, this effect in neutron star atmospheres is not as large as previously estimated. This suggests that neutron star spectral lines are sensitive to density and that their mass and radius can be obtained from spectral line fitting, which would help constrain the neutron star equation of state.

Protected spin-orbit induced absorption divergence in distorted Landau levels

The effect of spin-orbit (and Darwin) interaction on a 2D electron gas subject to a radial symmetric, inhomogeneous $1/r$-magnetic field is discussed analytically in a perturbative and non-perturbative manner. For this purpose, we investigate the radial Hall conductivity that emerges from an additional homogeneous electric field perturbation perpendicular to the 2D electron gas, which solely interacts via spin-orbit coupling. Numerical calculations of the absorptive spin-orbit spectra show for an ideal InSb electron gas a behaviour that is dominated by the localized (atomic) part of the distorted Landau levels. In contrast, however, we also find analytically that a (non-local) divergent static response emerges for Fermi energies close to the ionization energy in the thermodynamic limit. The divergent linear response implies that the external electric field is entirely absorbed outside the 2D electron gas by induced radial spin-orbit currents, as it would be the case inside a perfect conductor. This spin-orbit induced polarization mechanism depends on the effective $g^*$-factor of the material for which it shows a critical behaviour at $g^*_c=2$, where it abruptly switches direction. The diverging absorption relies on the presence of degenerate energies with allowed selection rules that are imposed by the radial symmetry of our inhomogeneous setup. We show analytically the presence of a discrete Rydberg-like band structure that obeys these symmetry properties. In a last step, we investigate the robustness of the spectra by solving analytically the Dirac equation expanded up to order $1/(mc)^2$. We find that the distorted Landau-levels, and thus the divergent spin-orbit polarization, remain protected with respect to slow changes of the applied $1/r$-magnetic field.

Robust Flexible Textile Tribovoltaic Nanogenerator via a 2D 2H‐MoS2/Ta4C3 Dynamic Heterojunction

AbstractThe tribovoltaic effect can convert semiconductor interfacial frictional mechanical energy into direct current (DC) electricity, but the flexibility and durability of semiconductor materials limit its application in wearable electronic. Herein, a robust flexible textile tribovoltaic nanogenerator is presented based on a 2D dynamic heterojunction of 2H‐MoS2/Ta4C3 (MTNG). During the friction process, a built‐in electric field (Eb) and an additional interfacial electric field (ECE) are generated in a continuous dynamic contact of 2H‐MoS2/Ta4C3, and through the 2H‐MoS2/Ta4C3 dynamic heterojunction, a significant number of electron‐hole pairs are excited and move directionally to generate a DC. The influences of mechanical pressure and sliding speed on output performance of MTNGs are systematically investigated. The MTNGs deliver excellent output power density (39.15 mW m2) and outstanding robustness (43 000 cycles). Ten MTNGs can be connected in series to obtain a DC voltage of 3.3 V and in parallel to obtain a DC current of 75 µA. Furthermore, the MTNGs can effectively power a variety of commercial electronic watches and calculators by harvesting human kinetic energy. A 2D dynamic heterojunction 2H‐MoS2/Ta4C3 DC nanogenerator is described and offers a workable option for the creation of flexible DC power sources and self‐powered wearable electronics.

Schottky effect on the wavelength threshold for the photo-detachment from charged metallic nanoparticles

Laser-stimulated electron photo-detachment (LSPD) from nanoscale dust particles is predicted to strongly depend on the particle size. A theory of the electron photo-detachment from charged spherical metallic nanoparticles is presented. This theory is relevant to laser-stimulated photo-detachment applied to measurements of charge of nanoparticles in plasmas. Our theory predicts that the charging of nanoparticles in plasma leads to the appearance of an additional electric field, causing a change in the potential barrier at the particle boundary and consequently, a change in the effective work function, due to the Schottky effect. In this case, the critical wavelength of the laser depends not only on the work function, but also on the charge of the nanoparticles and their size.

Catalyst-Free β-Ga2O3@a-Ga2O3 Core−Shell nanorod arrays grown on Si substrate for High-performance self-powered solar-blind photoelectrochemical photodetection

Self-powered photodetectors are recognized as one of the developing trends of next-generation optoelectronic devices. Particularly, a novel photoelectrochemical (PEC) type photodetectors have attracted a great deal of attention due to the advantages of low cost and self-powered capability. Herein, we construct, for the first time, solar-blind PEC-type photodetectors based on amorphous Ga2O3-covered β-Ga2O3 (denoted as β-Ga2O3@a-Ga2O3) core−shell nanorod arrays (NRAs) synthesized on silicon substrates using a simple one-step catalyst-free CVD method. The as-fabricated self-powered solar-blind photodetector has comprehensive photodetection performance in terms of a maximum responsivity of 48.4 mA/W, a high detectivity of 8.5 × 1011 Jones as well as fast response and recovery times (tres/trec = 125/160 ms) under 254 nm illumination with a light intensity of 0.1 mW/cm2, outperforming most of the reported Ga2O3 based PEC-type devices to date. Furthermore, the device shows good multicycle stability and repeatability. Such outstanding solar-blind photodetection performance is largely attributed to the superior crystalline quality of catalyst-free grown β-Ga2O3@a-Ga2O3 core−shell NRAs and the additional built-in electric field of a-Ga2O3 and β-Ga2O3 interface. This work provides a simple and feasible route for constructing Ga2O3-based PEC-type solar-blind photodetectors with high performance, stability and low cost.

Rapid electric field-enhanced crystallization of amorphous silicon thin films with an aluminum layer

A rapid aluminum induced crystallization (AIC) method of amorphous silicon (a-Si) thin film was suggested. A constant electrical current is supplied to an aluminum (Al) layer deposited on the a-Si thin film and anneals the Al/Si stack fast by Joule-heating. The Joule heating is presumed to expedite a-Si thin film crystallization. To investigate the crystallization mechanism, an in-situ temperature and reflectivity measurement was adopted during the process. The maximum crystallization temperature was 744.15 K, which was found to be similar to the typical furnace AIC process temperature and less than the Al/Si eutectic temperature of 850 K. The measured and calculated surface reflectivity demonstrated the rapid Al induced layer exchange behavior between Si and Al layers. The entire process was accomplished for only a few dozens of seconds. This rapid layer exchange is caused by sudden increase of temperature-dependent Al diffusion coefficient in a Si layer and additional electric field enhancement. The Raman peak of 519 cm−1 verified the formation of polycrystalline silicon (p-Si) after the Al etching process. Scanning electron microscopy images showed that the resulting p-Si structure was porous with an average pore size of around 1.2 μm.

Potential of an electric field generated during the scattering of an elastic wave on a fluid-filled vug in a porous rock

Propagation of elastic waves in porous fluid-saturated formations is often accompanied by electromagnetic radiation (seismoelectric effect), which has an electrokinetic nature. The magnitude of the generated electric current depends on the velocity of the relative flow between solid grains and a liquid in the primary pores. When the elastic wave is scattered by an inclusion, an additional liquid flow is generated. This flow induces a supplemental electromagnetic field.In this work, we have calculated an additional electric field generated by the scattering of an elastic wave on the vug (spherical cavity) located in an electrolyte-saturated poroelastic rock. The solution of the corresponding electrokinetic equations was obtained in the quasi-static approach. We have considered the problem for “open” and “closed” interfaces between the porous matrix and the vug. The solution was obtained for conducting and non-conducting fluids in the vug. The dependences of the magnitude of the generated electric field on the frequency and the rock parameters are presented.The results obtained demonstrate that the magnitude of the generated electric field depends considerably on the parameters of the rock (porosity and hydrodynamic permeability), as well as on the parameters of the fluid inside the inclusion (electric conductivity and bulk modulus). The calculations show that for an open interface the amplitude of the generated electric field is larger by more than an order of magnitude than for a closed interface. This is because the amplitude of the filtration flow near the vug surface is larger.

Spin-switching effect and giant magnetoresistance in quantum structure of monolayer MoS<sub>2</sub> nanoribbons with ferromagnetic electrode

Spintronics is a new type of electronics based on electron spin rather than charge as the information carrier, which can be stored and calculated by regulating and manipulating the spin. The discovery and application of the giant magnetoresistance effect opens the door to the application of electron spin properties. Realizing on-demand control of spin degree of freedom for spin-based devices is essential. The two-dimensional novel material, monolayer transition metal dichalcogenide (TMD) (MoS<sub>2</sub> is a typical example from the family of TMD materials), has become an excellent platform for studying spintronics due to its novel physical properties, such as direct band gap and strong spin-orbit coupling. Obtaining high spin polarization and achieving controllability of degrees of freedom are fundamental problems in spintronics. In this paper, we construct the monolayer zigzag MoS<sub>2</sub> nanoribbon quantum structure of electrically controlled ferromagnetic electrode to solve this problem. Based on the non-equilibrium Green’s function method, the regulation of the magnetic exchange field and electrostatic barrier on the spin transport in parallel configuration and anti-parallel configuration are studied. It is found that in the parallel structure, spin transport is obviously related to the magnetic exchange field, and 100% spin filtering can occur near the Fermi energy level to obtain pure spin current. When an additional electric field is applied to the middle region, the spin filtering effect is more significant. Therefore, the spin switching effect can be achieved by regulating the incident energy. In addition, it is also found that within a specific energy range, electrons in the parallel configuration are excited to participate in transport, while electrons in the anti-parallel structure are significantly inhibited. Consequently, a noticeable giant magnetoresistance effect can be obtained in this quantum structure. Moreover, it can be seen that the magnetic exchange field strength can effectively modulate the giant magnetoresistance effect. These results provide valuable theoretical references for the development of giant magnetoresistance devices and spin filters based on monolayer zigzag MoS<sub>2</sub> nanoribbons.

Effect of Acceptor Traps in GaN Buffer Layer on Breakdown Performance of AlGaN/GaN HEMTs.

In this paper, Silvaco TCAD software is used to simulate the buffer traps in AlGaN/GaN high electron mobility transistors (HEMTs), and its effects on the breakdown performance and key parameters of the devices are investigated by changing the position and concentration of the acceptor traps in the buffer layer. The results show that with the increase of trap concentration, the traps capture electrons and reduce the off-state leakage current, which can improve breakdown voltage of the devices. At the same time, as the trap concentration increases, the ionized traps make a high additional electric field near the drain edge, leading to the decrease of breakdown voltage. With the combined two effects above, the breakdown voltage almost ultimately saturates. When the source-to-gate (Access-S) region in the GaN buffer layer is doped alone, the minimum and most linear leakage current for the same trap concentrations are obtained, and the additional electric field has a relatively small effect on the electric field peak near the drain as the ionized traps are furthest from drain. All these factors make the breakdown voltage increase more controllably with the Access-S region doping, and it is a more potential way to improve the breakdown performance.

Improved performance of TiO2 nanoarray/BiOI heterojunction all-solid-state solar cells by incorporating BiFeO3 perovskite interlayer

The photovoltaic conversion of heterojunction solar cells relies on the interface properties between n-type and p-type semiconductors. N-type TiO2-nanoarray (NA), ferroelectric BiFeO3 interlayer, and p-type BiOI were used to fabricate a ternary bulk heterojunction using a solution-based method in this study. Solid-state solar cells of FTO/TiO2-NA/BiFeO3/BiOI/spiro-OMeTAD/Ag are constructed for the first time, and their photo-electric conversion performance is studied. The addition of a BiFeO3 interlayer at the interface between TiO2-NA and BiOI increased the solar cell open-circuit voltage (Voc) from 0.18 to 0.47 V and the short-circuit current (Jsc) from 0.29 to 0.54 μA/cm2, resulting in a nearly 5-fold increase in power conversion efficiency. The Kelvin Probe force microscope analysis confirmed that the polarization electric-field (Eself) generated by the BiFeO3 interlayer is directed toward BiOI, thereby increasing the surface potential and decreasing electron and hole back flows between TiO2 and BiOI. This additional electric field caused greater charge concentrations and a greater Voc. Furthermore, the Eself directed toward the BiOI increased the built-in electric field (Ebi) in the space charge area from TiO2 to BiOI, allowing for greater separation of photogenerated electrons and holes and thus raising the Jsc. The findings of this study suggested that manipulating internal electric fields via polarization could be an effective method for enhancing the performance of solar cells based on BiOI.

Electromagnetic field excitation during the scattering of an acoustic wave on an inhomogeneity in a poroelastic medium

Elastic wave propagation in porous media containing a movable fluid is frequently accompanied by electromagnetic field generation. Such field can be produced, for instance, by piezoelectric effect or have electrokinetic origin. In the present work, we consider the case of electrolyte-filled pores; thus, the generated electromagnetic field is associated with the electrokinetic effects. In this case, the magnitude of the electric current generated by the elastic wave is proportional to the magnitude of the relative displacement in the fluid and the solid phases. The presence of inhomogeneities in a porous medium can result in appearance of additional fluid flow with respect to the solid phase; thus, an additional electric field is generated. In our work, the magnitude of the electromagnetic field generated during the scattering of an elastic wave on a spherical porous inclusion in a porous matrix is calculated. The inclusion can differ from the matrix by the properties of the fluid in the pores or the properties of the elastic skeleton, such as porosity or permeability. The solution of the dynamic equations of electrokinetics is obtained by using the hypothesis that the inclusion size is much larger than the characteristic size of the pores. We have obtained the dependencies of the amplitude of the generated electromagnetic field on the inclusion parameters and the incident wave frequency. It was shown that the analysis of the additional electromagnetic field generated during the scattering of the elastic wave can provide some useful information about the structure of porous media.

Gradient bandgap modification for highly efficient carrier transport in antimony sulfide-selenide tandem solar cells

Antimony chalcogenides emerge as a type of efficient material for solar cells. In particular, antimony sulfide-selenide (SbSSe) has attracted significant interests based on their simple preparation, excellent photoelectric performance, and tunable bandgaps. In this study, by applying energy-band engineering technologies, we achieved carrier transport balance and light absorption balance for SbSSe single- and triple-junction solar cells, respectively. First in a single junction solar cell, the photoelectric conversion efficiency (PCE) of SbSSe solar cells is improved from 13.14% to 16.16% with a front-gradient Se content structure compared to a non-gradient Se content SbSSe solar cell. This improvement is attributed to the additional electric field induced by such a gradient bandgap, promoting the carrier motion. Consequently, the balance of carrier transport is realized by adjusting the drift velocities of holes and electrons simultaneously, thereby surpassing carrier recombination and improving the device parameters of short-circuit current density ( J sc ) and fill factor (FF). In a next step, an SbSSe of advanced gradient bandgap has been applied as the absorber layer of middle-cell in an antimony chalcogenide based triple-junction solar cell. Based on the high J sc and FF advantages of SbSSe sub-cells with front-gradient Se content structure, the uniform absorption of sunlight in each sub-cell and current matching of tandem solar cells could be easily realized. Eventually, the PCE of the triple-junction solar cell exhibits an enhancement from 17.34% to 19.51%. Our results demonstrate that the application of energy-band engineering technology can effectively improve device performance, providing theoretical guidance for the refined design and nanomanufacturing development of antimony chalcogenide solar cells. • Balanced carrier transport can be realized in a front-gradient SbSSe absorber. • Front-gradient SbSSe can form an additional electric field to promote hole transport. • A front-gradient SbSSe solar cell yields a high FF and J sc . • Applying a front-gradient SbSSe middle cell can enhance the triple-junction solar cell performance.

Surface-potential-modulated piezoresistive effect of core–shell 3C-SiC nanowires

The effect of surface potential on the carrier mobility and piezoresistance of core–shell silicon carbide nanowires (SiC NWs) was investigated to realize small and sensitive SiC-microelectromechanical systems sensors. The p-type cubic crystalline SiC (3C-SiC) NWs were synthesized via the vapor–liquid–solid method and coated with silicon dioxide (SiO2) or aluminum oxide (Al2O3) dielectric shells to form core–shell structured NWs with different surface potentials. Four-point bending devices (FBDs) with a field-effect transistor (FET) configuration integrating a single core–shell 3C-SiC NW as the FET channel were fabricated to apply an additional electric field and strain to the core–shell 3C-SiC NWs. The fixed oxide charge densities of the SiO2 and Al2O3 shells showed positive and negative values, respectively, which were equivalent to electric fields of the order of several hundred thousand volt per centimeter in absolute values. In the core–shell 3C-SiC NWs with originally low impurity concentrations, the electric field induced by the fixed oxide charge of the shells can determine not only the electrical conduction but also the charge carriers in the NWs. Bending tests using the FBDs showed that the piezoresistive effect of the SiO2-coated NW was almost the same as that of the as-grown 3C-SiC NW reported previously, regardless of the gate voltage, whereas that of the Al2O3-coated NW was considerably enhanced at negative gate voltages. The enhancement of the piezoresistive effect was attributed to the piezo-pinch effect, which was more pronounced in the NW, where the carrier density at the core–shell interface is enhanced by the electric field of the dielectric.

Planar heterojunction perovskite solar cell with graded energy band architecture via fast-drying spray deposition

The fast-drying spray deposition (FDSD) technique for perovskite solar cells (PSCs) is developed to enable the stacking of perovskite absorbers with different work functions, which allows the creation of an additional built-in electric field at the interface during the fermi level realignment process upon contact. FDSD is functional under high relative humidity (RH) ambiance and by design, deposits dry film without the need for post-deposition annealing treatment. Based on a spray coating process, FDSD is also highly scalable. Leveraging FDSD’s multilayer deposition capability, this work explores the implementation of graded energy band architectures to achieve PSCs with enhanced carrier extraction and photovoltaic performances. To demonstrate the potential benefit of this approach, two triple cation mixed halide perovskite formulas are chosen. The two formulas, when stacked together in correct order, produce a heterojunction PSC device with an extra built-in electric field, which helps drift charge carriers towards desired electrodes. The architecture with the proper energy band alignment therefore exhibits enhanced carrier extraction efficiency and, despite being subjected to over 60–80% RH during fabrication, reaches the mean power conversion efficiency (PCE) of 7.4%, with the maximum value of 9.5%. The average PCE translates to over 9.9% and 10.3% improvements over the devices based on the two constituent formulas individually. FDSD demonstrates great flexibility i.e., in-humid-air fabrication process and requiring no post annealing treatments, thereby enabling extremely robust and scalable stacked architecture PSCs with low cost and good performance.

Numerical simulation of air DBD under standard atmospheric pressure

In order to study the mechanism of dielectric barrier discharge (DBD) producing non-equilibrium plasma, the DBD equipment was simplified into a one-dimensional model. The AC power supply voltage was set as 18 kV, the frequency was set as 10 kHz, and the discharge medium was N2 and O2 with a mass fraction of 4:1 to simulate the air. The impact cross-section, electron mobility and initial electron temperature of the discharge reaction were determined by BOLSIG+. The electric potential field diagram, voltage current relation diagram, electron density diagram, temperature distribution diagram and electron energy distribution function EEDF diagram are obtained. The results show that the electric field reaches the maximum near the gap sheath. Due to the generation of an additional electric field, the current density reaches the maximum at the rising edge of the air gap voltage. The continuous ionization of air particles in the discharge process leads to the accumulation of electrons and the formation of electron collapse, which leads to the increase in electron density and the decrease in electron temperature. As the reduced electric field E/N increases, the proportion of high-energy electrons in the total electron number increases. At this time, the reaction of non-equilibrium plasma intensifies, and more active substances can be produced.