Effect of surface charge trapping in dielectric barrier discharge

Li, C.R.; Li, M.; Zhan, Huamao; Wang, X.X.

doi:10.1109/plasma.2009.5227647

Cited by 4 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Finally, we note that the temporal profiles of electron emission computed in this section are qualitatively consistent with the observed temporal profiles of plasma formation reported in the literature [32][33][34][35]. We have shown that electron transfer from the dielectric to the argon region under an AC voltage is time-dependent, and that the dielectric region can provide electrons for plasma generation.…”

Section: Electron Transfer At Constant Maximum Electric Fieldsupporting

confidence: 89%

“…In the case of dielectric-gas-dielectric systems under AC voltage, degeneracies between localized states within and outside the dielectric surface appear due to time-dependent energy level crossing, leading to the possibility of time-dependent electron transfer. The temporal profile of current-voltage phase lag, as well as surface charge accumulation and depletion obtained from our computations using simple energy level crossing arguments, are consistent with experimental observations in the literature [32][33][34][35], but quantitative agreement with experiments requires more detailed computations coupling electron transfer from dielectric surfaces with the kinetics of plasma formation, and are beyond the scope of this work. difference is applied, a linear potential drop is expected across various insulating parts of the device, according to their relative permittivity r , and we are interested in the timedependent transfer of electrons from the dielectric into the gaseous argon under a timedependent potential V ext (t).…”

Section: Introductionsupporting

confidence: 86%

“…Finally, we note that electron emission from surface walls is a necessary but insufficient condition for plasma formation. As such, the computed temporal profiles of electron transfer are consistent with, and provide partial predictions for, the observed temporal profiles of plasma formation in the literature [32][33][34][35].…”

Section: Electron Transfer At Constant Maximum Electric Fieldsupporting

confidence: 79%

“…The Finally, we note that the total number of electrons in the isolated system is held constantas such, electron transfers result in charge depletion (holes) and accumulation (electrons) on the dielectric surfaces. The computation of charge depletion and accumulation complements recent phenomenological and experimental investigations of surface effects such as surface charge accumulation and depletion, memory effects on microdischarge formation, and surface charge transport [32,34,35]. However, surface charges can also be transported towards metallic contacts, and recent works have investigated electron absorption and subsequent transport in dielectric materials, and the associated effects of phonons and impurities [36][37][38][39].…”

Section: Introductionmentioning

confidence: 72%

See 3 more Smart Citations

Dynamical level-crossing model for the time-dependent electron emission from dielectric surfaces in symmetric dielectric barrier discharges

Ghale

Johnson

2019

Phys. Rev. B

View full text Add to dashboard Cite

In field emission plasmas, electrons that initiate plasma formation come from the surface of a metallic electrode, or wall, with emission controlled by the electron-work function of the wall, and can be computed via the Fowler-Nordheim formula. Impinging ions modify the rate at which electrons leave the surface, and are accounted via the coefficient of secondary electron emission. However, in the case of dielectric surfaces, the microscopic mechanism by which electrons are emitted is not as well understood. While simulations of dielectric barrier discharge plasmas assume an initial density of electrons in a time-dependent simulation, whether the presence of electrons is a necessary ambient condition or whether it is a result of emission from a surface is not clear. This is particularly relevant in the context of micro and nanoscale plasma generators when surface-related effects become more important. Here we consider electron emission from dielectric surfaces in the context of dielectric barrier discharges. The configuration of interest consists of two parallel-plate metallic electrodes, each covered by a dielectric layer. Assuming that the initial electrons for plasma formation arise from the surface, we compute the rate of charge transfer from surfaces, which is a necessary, but not sufficient, condition for plasma formation. The novelty of this work is the application of the theory of nonadiabatic transitions (dynamical level-crossing) to the problem of electron emission from dielectric surfaces in dielectric barrier discharges. The microscopic model of electron transfer described here has potential applications in the design of micro and nano-scale plasma generators.

show abstract

Section: Electron Transfer At Constant Maximum Electric Fieldsupporting

confidence: 89%

Section: Introductionsupporting

confidence: 86%

Section: Electron Transfer At Constant Maximum Electric Fieldsupporting

confidence: 79%

Section: Introductionmentioning

confidence: 72%

See 2 more Smart Citations

Dynamical level-crossing model for the time-dependent electron emission from dielectric surfaces in symmetric dielectric barrier discharges

Ghale

Johnson

2019

Phys. Rev. B

View full text Add to dashboard Cite

show abstract

“…As the barrier increases in thickness, the capacitance due to the barrier decreases resulting in a greater voltage drop across the barrier, and less voltage applied across the gas gap. This results in a reduced power applied to the plasma region, reducing the electron density and chance of collisions in the gas space, and leading to lower concentration of ions and excited atoms formed in the plasma [57][58][59][60]. It was observed that the MB degradation using the microfluidic device was greatest using an overall 2 mm barrier thickness, with 50 µm channel depth and 35 µL/min as the liquid flow rate.…”

Section: Effect Of Barrier Thicknessmentioning

confidence: 99%

A Microfluidic Atmospheric-Pressure Plasma Reactor for Water Treatment

Patinglag

Sawtell

Iles

et al. 2019

Plasma Chem Plasma Process

View full text Add to dashboard Cite

A dielectric barrier discharge microfluidic plasma reactor, operated at atmospheric pressure, was studied for its potential to treat organic contaminants in water. Microfluidic technology represents a compelling approach for plasma-based water treatment due to inherent characteristics such as a large surface-area-to-volume ratio and flow control, in inexpensive and portable devices. The microfluidic device in this work incorporated a dielectric barrier discharge generated in a continuous gas flow stream of a two-phase annular flow regime in the microchannels of the device. Methylene blue in solution was used to investigate plasma induced degradation of dissolved organic compounds within the microfluidic device. The relative degradation rates of methylene blue were influenced by the residence time of the sample solution in the discharge zone, type of gas applied, channel depth and flow rate. Increasing the residence time inside the plasma region led to higher levels of degradation. Oxygen was found to be the most effective gas, with the spectra obtained using Liquid Chromatography-Mass Spectroscopy indicating the most significant degradation. By reducing the channel depth from 100 to 50 µm, the best results were obtained, achieving a greater than 97% level of methylene blue degradation. The microfluidic system presented here demonstrates proof-of-concept that plasma technology can be utilised as an advanced oxidation process for water treatment, with the potential to eliminate water treatment consumables such as filters and disinfectants.

show abstract

Streamer dynamics and charge self‐erasing of two counter‐propagating plasmas in repetitively pulsed surface dielectric barrier discharge

et al. 2022

View full text Add to dashboard Cite

The streamer dynamics and charge self‐erasing of two counter‐propagating plasmas generated by repetitively pulsed surface dielectric barrier discharge are investigated using electrical and optical diagnosis, and a two‐dimensional fluid model. Three distinct discharge phases of primary, transitional and secondary streamers are identified in a single‐pulse discharge through the time‐resolved plasma images. Moreover, a merging phenomenon of the two opposing primary streamers is observed at the middle position of the discharge gap. Compared to the first pulse, a low streamer propagation velocity of the primary streamer is measured during the subsequent discharge process due to the limitation of residual surface charges left by the previous discharge. No significant differences of the transferred charge and the deposited energy are obtained in the sequential pulses at a discharge gap of 9 mm. Numerical simulations show that a reduction for the plasma intensity of the approached two primary streamers is attributed by the accumulated charge on the dielectric surface and gathered positive charges in the streamer head. Numerical and experimental studies indicate that the residual charges can be erased by the secondary streamer through the drifted electrons, namely that a phenomenon of charge self‐erasing can be realized in the individual pulse.

show abstract

Effect of surface charge trapping in dielectric barrier discharge

Cited by 4 publications

References 0 publications

Dynamical level-crossing model for the time-dependent electron emission from dielectric surfaces in symmetric dielectric barrier discharges

Dynamical level-crossing model for the time-dependent electron emission from dielectric surfaces in symmetric dielectric barrier discharges

A Microfluidic Atmospheric-Pressure Plasma Reactor for Water Treatment

Streamer dynamics and charge self‐erasing of two counter‐propagating plasmas in repetitively pulsed surface dielectric barrier discharge

Contact Info

Product

Resources

About