Klose, S. J., Manfred, K. M. orcid.org/0000-0002-6850-1560, Norman, H. C. et al. (2 more authors) (2020) The spatial distribution of HO2in an atmospheric pressure plasma jet investigated by cavity ring-down spectroscopy. Plasma Sources Science and Technology. 085011. ISSN 0963-0252
Abstract
Cold atmospheric pressure plasma jets make important contributions to a range of fields, such as materials processing and plasma medicine. In order to optimise the effect of those plasma sources, a detailed understanding of the chemical reaction networks is pivotal. However, the small diameter of plasma jets makes diagnostics challenging. A promising approach to obtain absolute number densities is the utilisation of cavity-enhanced absorption spectroscopy methods, by which line-of-sight averaged densities are determined. Here, we present first measurements on how the spatial distribution of HO2 in the effluent of a cold atmospheric pressure plasma jet can be obtained by cavity ring-down spectroscopy in an efficient way. Instead of recording fully wavelength resolved spectra, we will demonstrate that it is sufficient to measure the absorption coefficient at two wavelengths, corresponding to the laser being on and off the molecular resonance. By sampling the effluent from the 1.6 mm diameter nozzle in the radial direction at various axial positions, we determined that the distances over which the HO2 density was distributed were (3.9 ± 0.5) mm and (6.7 ± 0.1) mm at a distance of 2 mm and 10 mm below the nozzle of the plasma jet, respectively. We performed an Abel inversion in order to obtain the spatial distribution of HO2 that is presented along the symmetry axis of the effluent. Based on that localised density, which was (4.8 ± 0.6) ⋅ 1014 cm-3 at the maximum, we will discuss the importance of the plasma zone for the production of HO2.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2020 The Author(s). |
Keywords: | atmospheric pressure plasma jet,cavity ring-down spectroscopy,density of transient species,hydroperoxyl radical,spatial distribution |
Dates: |
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Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Chemistry (York) |
Depositing User: | Pure (York) |
Date Deposited: | 30 Sep 2020 12:50 |
Last Modified: | 16 Dec 2024 00:13 |
Published Version: | https://doi.org/10.1088/1361-6595/aba206 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1088/1361-6595/aba206 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:166206 |
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Filename: Klose_2020_Plasma_Sources_Sci._Technol._29_085011.pdf
Description: The spatial distribution of HO2 in an atmospheric pressure plasma jet investigated by cavity ring-down spectroscopy
Licence: CC-BY 2.5