Plasma parameters of argon and argon/molecular gas mixture plasmas produced in microwave discharge

Dobrea, Remus-Sorin; Mihăilă, Ilarion; Popa, G.

doi:10.1016/j.mseb.2013.04.003

Cited by 5 publications

(2 citation statements)

References 23 publications

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“…The different CO 2 conversion efficiencies may be linked to the different gas temper ature in these gas mixtures measured in the post-discharge and given in figure 4. It was reported that the presence of H 2 significantly decreases electron temperature in the gas mixture [31], which should impair vibrational excitation of CO 2 . The higher gas temperature associated with the vibrational-translational (VT) relaxation processes reduces the population of the CO 2 vibrational levels.…”

Section: Effect Of the Gas Mixturementioning

confidence: 99%

An overview of CO₂conversion in a microwave discharge: the role of plasma-catalysis

Chen

Britun

Godfroid

et al. 2017

J. Phys. D: Appl. Phys.

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An overview of the recent progress on plasma-assisted CO2 conversion in microwave discharges is given. Special attention is devoted to the results obtained using plasma catalysis, which are compared to the plasma-only CO2 decomposition cases. The effects of plasma operating conditions, catalyst preparation methods, nature of plasma activation gas, gas mixture, as well as the NiO content on the TiO2 surface on CO2 conversion and its energy efficiency are discussed. A significant improvement in CO2 conversion is obtained with a NiO/TiO2 catalyst activated in Ar plasma, when the NiO content is about 10 wt.%. The catalyst characterization data show that Ar plasma treatment results in a higher density of oxygen vacancies and a comparatively more uniform distribution of NiO on the TiO2 surface, which strongly influence CO2 conversion and its energy efficiency. The dissociative electron attachment of CO2 at the catalyst surface enhanced by the oxygen vacancies and by plasma electrons may also explain the increase in conversion and energy efficiencies. A mechanism for the plasma-catalytic CO2 conversion at the surface of an Ar plasma-threated catalyst is proposed.

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Section: Effect Of the Gas Mixturementioning

confidence: 99%

An overview of CO₂conversion in a microwave discharge: the role of plasma-catalysis

Chen

Britun

Godfroid

et al. 2017

J. Phys. D: Appl. Phys.

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“…At atmospheric pressure, it is hard to distinguish the dominant processes from the above reactions. However, there is some consideration that at atmospheric pressure the electron temperature is not as high as that at low pressure [37][38][39][40], and then the electron impact dissociation will contribute less than the other processes. Because the spectrum in figure 4(a) has presented strong emission intensity from the first negative nitrogen band and the discharge photograph in figure 1 exhibits prominent afterglow in the N 2 -Ar plasma, it is noted that there are abundant ionized nitrogen molecules and nitrogen metastable states produced in the plasma torch [11].…”

Section: Variation Of the Typical Spectral Lines Emanating From N +mentioning

confidence: 99%

Spectroscopic diagnosis of an atmospheric-pressure waveguide-based microwave N₂–Ar plasma torch

Chen

Zhang

et al. 2015

Plasma Sources Sci. Technol.

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An atmospheric-pressure N 2 -Ar plasma is investigated by means of optical emission spectroscopic diagnosis concerning the variation of its fundamental parameters, electron density and plasma temperature, and concentrations of ionized molecular nitrogen, atomic nitrogen, and excited argon with the tuning variables, such as the input power and the ratio of N 2 in N 2 -Ar mixture gas, in the discharge region of the plasma torch. Moreover, qualitative discussions are delivered with respect to the mechanisms for nitrogen dissociation and influence of the Ar component on the N 2 plasma discharge at atmospheric pressure.

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Spectroscopic study of CO2 and CO2–N2 mixture plasma using dielectric barrier discharge

et al. 2019

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Nowadays, increasing concentration of CO2 in the atmosphere is a major threat for the environment and is a main reason for global warming. Variation in gas temperature and dissociation of CO2 into its by-products (CO and O) in a home-made dielectric barrier discharge (DBD) reactor have been reported as a function of discharge parameters, i.e., applied voltage and gas flow rate. To estimate the dissociation fraction of CO2 in the DBD reactor, the optical emission actinometry technique is employed in which 5% N2 is used as an actinometer. Emission lines of the Angstrom band of CO at 451.09 nm (B1∑ +v′=0−A1π, v″=0) and the 2nd positive system of N2 at 337.01 nm (C3πuv′=0−B3πg,v″=0) are used for actinometry measurements. To estimate the rate coefficients used in actinometry measurements, gas temperature is measured using the Boltzmann plot technique, from the rotational spectra of the Q-branch of the Angstrom band CO (0–1). To avoid discrepancy in gas temperature measurements, rotational temperature of the 2nd positive system, the N2 (0–1) band, is also measured. For this, synthetic spectra have been fitted over the experimentally recorded spectrum of the N2 (0–1) band. A slight difference in gas temperature has been noted for the Angstrom band of CO and the 2nd positive system of nitrogen. Conversely, an increasing trend in the dissociation fraction of CO2 with an increase in the applied voltage is noted. About 34% dissociation fraction is achieved for 10 kV applied voltage at a flow rate of 25 SCCM. With an increase in the gas flow rate (25–200 SCCM), a decrease in the dissociation fraction of CO2 from 34% to 11% is noted.

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Plasma parameters of argon and argon/molecular gas mixture plasmas produced in microwave discharge

Cited by 5 publications

References 23 publications

An overview of CO₂conversion in a microwave discharge: the role of plasma-catalysis

An overview of CO₂conversion in a microwave discharge: the role of plasma-catalysis

Spectroscopic diagnosis of an atmospheric-pressure waveguide-based microwave N₂–Ar plasma torch

Spectroscopic study of CO2 and CO2–N2 mixture plasma using dielectric barrier discharge

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Plasma parameters of argon and argon/molecular gas mixture plasmas produced in microwave discharge

Cited by 5 publications

References 23 publications

An overview of CO2conversion in a microwave discharge: the role of plasma-catalysis

An overview of CO2conversion in a microwave discharge: the role of plasma-catalysis

Spectroscopic diagnosis of an atmospheric-pressure waveguide-based microwave N2–Ar plasma torch

Spectroscopic study of CO2 and CO2–N2 mixture plasma using dielectric barrier discharge

Contact Info

Product

Resources

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An overview of CO₂conversion in a microwave discharge: the role of plasma-catalysis

An overview of CO₂conversion in a microwave discharge: the role of plasma-catalysis

Spectroscopic diagnosis of an atmospheric-pressure waveguide-based microwave N₂–Ar plasma torch