Atomic oxygen formation in a radio-frequency driven micro-atmospheric pressure plasma jet

Abstract

Atomic oxygen formation in a radio-frequency driven micro-atmospheric pressure plasma jet is investigated using both advanced optical diagnostics and numerical simulations of the dynamic plasma chemistry. Laser spectroscopic measurements of absolute densities of ground state atomic oxygen reveal steep gradients at the interface between the plasma core and the effluent region. Spatial profiles resolving the interelectrode gap within the core plasma indicate that volume processes dominate over surface reactions. Details of the production and destruction processes are investigated in numerical simulations benchmarked by phase-resolved optical emission spectroscopy. The main production mechanisms are electron induced and hence most efficient in the vicinity of the plasma boundary sheath, where electrons are energized. The destruction is driven through chemical heavy particle reactions. The resulting spatial profile of atomic oxygen is relatively flat. The power dependence of the atomic oxygen density obtained by the numerical simulation is in very good agreement with the laser spectroscopic measurements.

Hydrogen Peroxide Production in an Atmospheric Pressure RF Glow Discharge: Comparison of Models and Experiments

“…Clearly, radical species densities and the electron density are both of key importance for this balance. To find an approximation for the electron density, recent results of [39] for a RF micro atmospheric plasma jet investigating atomic oxygen formation have been reported in the order of n e = 10 11 cm −3 for the power density in our case. For the case of He -H 2 O, the results of the 1 D model (see further) yields n e = 5 · 10 10 cm −3 .…”

Methods of gas purification and effect on the ion composition in an RF atmospheric pressure plasma jet investigated by mass spectrometry

“…The micro atmospheric pressure plasma jet (μ-APPJ) has been in the focus of many studies in the past and is described in great detail in [4,[26][27][28][29][30]. Here, a short description of the recent design will be given together with the operating procedure.…”

Impact of plasma jet vacuum ultraviolet radiation on reactive oxygen species generation in bio-relevant liquids

“…The gas and plasma phase chemistry of these jets has been investigated quite thoroughly, and many processes have been already understood. [10][11][12][13] For the field of plasma medicine, however, a further diagnostic step is required: When biological systems are plasma treated, these systems usually require a liquid surrounding, such as cell culture medium for in vitro studies. 14 Also under physiological conditions in vivo, a liquid environment nearly always surrounds living tissue.…”