Analysis of NOx production in an RF kINPen and a µs driven plasma gun

Summary form only given. NO_x and associated acids are investigated with regards to their role for biomedical application. NO_x are produced by two different plasma sources, a RF kINPen and a μS Plasma gun, both are cold atmospheric pressure plasma jets. The first one is powered by a radio frequency voltage [1, 2] of 1 MHz, the second one is a dielectric barrier discharge powered by a μs pulse voltage [3, 4]. For these two sources, NO_x are produced by many complex chemicals reactions occurring in the interaction of the active plume with surrounding air. With the mid infrared quantum cascade laser absorption spectroscopy [1], we are able to measure the absolute density of NO₂ and O₃ produced by both plasma sources. Correlating the measurements in situ with optical emission spectroscopy, great differences in the excitation processes of fundamental species such as O, N₂, OH, N₂ and N₂⁺ can be observed. With a parametrical study, varying the voltage and the pulse repetition frequency, we are able to modulate the NO₂ densities production from a few tens to a few hundreds of ppb. Such parametric analysis also shows that large variations in the population of the different molecular bands of the NO gamma system, are associated with the plasma gun operation regime. These physical parameters play a major role in the NO_x production and yield vital clues to discriminate major kinetic reactions involved in the NO production and in relation with future numerical simulations.