Optical emission study of nonthermal plasma confirms reaction mechanisms involving neutral rather than charged species

doi:10.1063/1.2434002

Title: Optical emission study of nonthermal plasma confirms reaction mechanisms involving neutral rather than charged species

Full Record
Other Related Research

Abstract

Charge transfer reactions are commonly used to explain NO{sub x} conversion in nonthermal plasma. An analysis of optical emission spectra induced by pulsed corona discharge in NO{sub x}-containing argon suggests that, in fact, the contribution of charge transfer reactions to NO{sub x} conversion in nonthermal plasma is negligible. During electrical discharge in such gas mixtures, NO(B), an electronic excited state of NO formed due to the dissociative recombination reactions of NO{sub 2}{sup +} and N{sub 2}O{sup +} and the optical emission of NO(B) could be a proof that cations are responsible for NO{sub x} conversion. However, the optical emission of NO(B) is not observed, leading to the conclusion that cations are not involved to any measurable degree. Therefore, charge transfer reactions cannot play a significant role in nonthermal plasma largely because the cations are neutralized with electrons before any charge transfer reactions can occur and concentrations of radicals are far higher than those of cations, which inhibits charged particle reactions. Instead, neutral active species, such as atoms, molecular fragments, and excited molecules, are the major active species contributing to nonthermal plasma reactions.

Authors:

Zhao, Gui-Bing; Argyle, Morris D.; Radosz, Maciej ^[1]

Department of Chemical and Petroleum Engineering, University of Wyoming, Laramie, Wyoming 82071-3295 (United States)

Publication Date:: Thu Feb 01 00:00:00 EST 2007

OSTI Identifier:: 20982664

Resource Type:: Journal Article

Resource Relation:: Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 3; Other Information: DOI: 10.1063/1.2434002; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ARGON; CATIONS; CHARGE EXCHANGE; CHARGED-PARTICLE REACTIONS; CORONA DISCHARGES; ELECTRONS; EMISSION SPECTRA; EXCITED STATES; NITRIC OXIDE; NITRITES; PLASMA; PLASMA DIAGNOSTICS; REACTION KINETICS; RECOMBINATION; TRANSFER REACTIONS

Citation Formats


                    Zhao, Gui-Bing, Argyle, Morris D., and Radosz, Maciej. Optical emission study of nonthermal plasma confirms reaction mechanisms involving neutral rather than charged species.  United States: N. p., 2007. 
        Web.  doi:10.1063/1.2434002.

Copy to clipboard


                    Zhao, Gui-Bing, Argyle, Morris D., & Radosz, Maciej. Optical emission study of nonthermal plasma confirms reaction mechanisms involving neutral rather than charged species.  United States.  doi:10.1063/1.2434002.

Copy to clipboard


                    Zhao, Gui-Bing, Argyle, Morris D., and Radosz, Maciej. Thu .  
        "Optical emission study of nonthermal plasma confirms reaction mechanisms involving neutral rather than charged species".  United States.  
        doi:10.1063/1.2434002.

Copy to clipboard


                    
@article{osti_20982664,

  title        = {Optical emission study of nonthermal plasma confirms reaction mechanisms involving neutral rather than charged species},

  author       = {Zhao, Gui-Bing and Argyle, Morris D. and Radosz, Maciej},

  abstractNote = {Charge transfer reactions are commonly used to explain NO{sub x} conversion in nonthermal plasma. An analysis of optical emission spectra induced by pulsed corona discharge in NO{sub x}-containing argon suggests that, in fact, the contribution of charge transfer reactions to NO{sub x} conversion in nonthermal plasma is negligible. During electrical discharge in such gas mixtures, NO(B), an electronic excited state of NO formed due to the dissociative recombination reactions of NO{sub 2}{sup +} and N{sub 2}O{sup +} and the optical emission of NO(B) could be a proof that cations are responsible for NO{sub x} conversion. However, the optical emission of NO(B) is not observed, leading to the conclusion that cations are not involved to any measurable degree. Therefore, charge transfer reactions cannot play a significant role in nonthermal plasma largely because the cations are neutralized with electrons before any charge transfer reactions can occur and concentrations of radicals are far higher than those of cations, which inhibits charged particle reactions. Instead, neutral active species, such as atoms, molecular fragments, and excited molecules, are the major active species contributing to nonthermal plasma reactions.},

  doi          = {10.1063/1.2434002},

  journal      = {Journal of Applied Physics},

  number       = 3,

  volume       = 101,

  place        = {United States},

  year         = {Thu Feb 01 00:00:00 EST 2007},

  month        = {Thu Feb 01 00:00:00 EST 2007}

}

Copy to clipboard

Journal Article:

DOI: 10.1063/1.2434002

Other availability

Find in Google Scholar

Search WorldCat to find libraries that may hold this journal

Save / Share:

Export Metadata

Save to My Library

Similar records in OSTI.GOV collections:

Relativistic pair beams from TeV blazars: A source of reprocessed GeV emission rather than intergalactic heating

Journal Article Sironi, Lorenzo ; Giannios, Dimitrios, E-mail: lsironi@cfa.harvard.edu, E-mail: dgiannio@purdue.edu - Astrophysical Journal

The interaction of TeV photons from blazars with the extragalactic background light produces a relativistic beam of electron-positron pairs streaming through the intergalactic medium (IGM). The fate of the beam energy is uncertain. By means of two- and three-dimensional particle-in-cell simulations, we study the nonlinear evolution of dilute ultra-relativistic pair beams propagating through the IGM. We explore a wide range of beam Lorentz factors γ {sub b} >> 1 and beam-to-plasma density ratios α << 1, so that our results can be extrapolated to the extreme parameters of blazar-induced beams (γ {sub b} ∼ 10{sup 6} and α ∼ 10{supmore »« less
DOI: 10.1088/0004-637X/787/1/49
Characterization of neutral species densities in dual frequency capacitively coupled photoresist ash plasmas by optical emission actinometry

Journal Article Worsley, M. A. ; Bent, S. F. ; Fuller, N. C. M. ; ... - Journal of Applied Physics

Reactive neutral species densities for various conditions in dual frequency capacitively coupled discharges of Ar/O{sub 2}, Ar/N{sub 2}, and Ar/H{sub 2} were determined using optical emission spectroscopy, Kr actinometry, and modeling. The reactive neutral species probed in this work include O, O{sub 2}, N, N{sub 2}, H, and H{sub 2}. Densities are reported as a function of pressure (5-60 mTorr), percent Ar in the feed gas (1%-86%), source power (50-800 W), and bias power (0 W, 200 W). It was found that increasing the pressure from 5 to 60 mTorr resulted in order of magnitude increases in atomic species densitiesmore »« less
DOI: 10.1063/1.2358303
Numerical study of an electrostatic plasma sheath containing two species of charged dust particles

Journal Article Foroutan, G. ; Akhoundi, A. - Journal of Applied Physics

A multi-fluid model is used to study the dynamics of a dusty plasma sheath consists of electrons, ions, and two species of charged dust particles, i.e., nano-size and micron-size particles. It is found that, when the sheath is dominated by the nano-size dust grains, spatially periodic fluctuations are developed in the profiles of the sheath potential, and the number density and velocity of the plasma and dust particles. Due to inertial effects, the fluctuations in the parameters of the micron-size grains are much lower than those of the other parameters. The competition between the electric and ion drag forces playsmore »« less
DOI: 10.1063/1.4755798
Investigation of InP etching mechanisms in a Cl{sub 2}/H{sub 2} inductively coupled plasma by optical emission spectroscopy

Journal Article Gatilova, L. ; Bouchoule, S. ; Guilet, S. ; ... - Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films

Optical emission spectroscopy (OES) has been used in order to investigate the InP etching mechanisms in a Cl{sub 2}-H{sub 2} inductively coupled plasma. The authors have previously shown that anisotropic etching of InP could be achieved for a H{sub 2} percentage in the 35%-45% range where the InP etch rate also presents a local maximum [J. Vac. Sci. Technol. B 24, 2381 (2006)], and that anisotropic etching was due to an enhanced passivation of the etched sidewalls by a silicon oxide layer [J. Vac. Sci. Technol. B 26, 666 (2008)]. In this work, it is shown that this etching behaviormore »« less
DOI: 10.1116/1.3071950
Sagdeev potential analysis for positively charged dust grains in nonthermal dusty plasma near Mars

Journal Article El-Taibany, W. F. ; Wadati, Miki - Physics of Plasmas

The existence of nonlinear dust acoustic (DA) solitary waves for positive dust grains is examined in a dusty plasma (DP). Four charging currents are considered: photoemission, secondary electrons, as well as the electron and ion currents. The nonthermal ion charging current is presented for the first time. Introducing nonthermal ions in the DP system aids in increasing the net positive dust charge, though raising their temperature goes in the opposite direction. There is a maximum value of the ambient plasma potential allowing positive dust charges. The energy equation for the DP system is obtained. The allowed Mach number regime ismore »« less
DOI: 10.1063/1.2784764

Similar Records