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

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:
; ;  [1]
  1. Department of Chemical and Petroleum Engineering, University of Wyoming, Laramie, Wyoming 82071-3295 (United States)
Publication Date:
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.
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.
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.
@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}
}
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