HO2 reaction kinetics in an atmospheric pressure plasma jet determined by cavity ring-down spectroscopy. (25th September 2018)

• Record Type: Journal Article
• Authors: Gianella, M; Reuter, S; Press, S A; Schmidt-Bleker, A; Helden, J H van; Ritchie, G A D
• Is Part Of: Plasma sources science & technology. Volume 27:Number 9(2018:Sep.)
• Publication Date: 2018-09-25
• Subjects: atmospheric pressure plasma jet -- cavity ring-down spectroscopy -- hydroperoxyl radical; Plasma (Ionized gases) -- Periodicals; 530.44
• DOI: 10.1088/1361-6595/aadf01
• Languages: English
• ISSNs: 0963-0252

Abstract

Abstract: Hydroperoxyl ( HO 2 ) is detected in the effluent of an atmospheric pressure plasma jet (PJ) by cavity ring-down absorption spectroscopy. Laser radiation at 1506.4 nm is used to determine HO 2 concentrations directly in the plasma effluent at atmospheric pressure as well as indirectly after sampling through a pinhole and expanding to 5.33 kPa . To unravel the HO 2 reaction kinetics, the argon feed gas is humidified and the PJ is equipped with a gas curtain device that controls the surrounding atmosphere. Varying the curtain gas composition from pure nitrogen to pure oxygen leads to a five to six-fold increase in HO 2 concentrations towards higher oxygen concentrations. A reaction kinetics model considering near-field and far-field reactions describes the reaction pathways that determine the hydroperoxyl concentration and is in good agreement with the measurements at both low and atmospheric pressure.