Quantitative measurements of ground state atomic oxygen in atmospheric pressure surface micro-discharge array. (9th May 2017)

• Record Type: Journal Article
• Authors: Li, D; Kong, M G; Britun, N; Snyders, R; Leys, C; Nikiforov, A
• Is Part Of: Journal of physics. Volume 50:Number 21(2017)
• Publication Date: 2017-05-09
• Subjects: surface discharge -- two photon absorption laser-induced fluorescence -- atomic oxygen -- atmospheric pressure discharge; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/aa6c44
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: The generation of atomic oxygen in an array of surface micro-discharge, working in atmospheric pressure He/O2 or Ar/O2 mixtures, is investigated. The absolute atomic oxygen density and its temporal and spatial dynamics are studied by means of two-photon absorption laser-induced fluorescence. A high density of atomic oxygen is detected in the He/O2 mixture with up to 10% O2 content in the feed gas, whereas the atomic oxygen concentration in the Ar/O2 mixture stays below the detection limit of 10 13 cm −3 . The measured O density near the electrode under the optimal conditions in He/1.75% O2 gas is 4.26 × 10 15 cm −3 . The existence of the ground state O (2 p 4 3 P ) species has been proven in the discharge at a distance up to 12 mm away from the electrodes. Dissociative reactions of the singlet O2 with O3 and deep vacuum ultraviolet radiation, including the radiation of excimer He 2 ∗, are proposed to be responsible for O (2 p 4 3 P ) production in the far afterglow. A capability of the surface micro-discharge array delivering atomic oxygen to long distances over a large area is considered very interesting for various biomedical applications.