The effect of three different methods of adding O2 additive on O concentration of atmospheric pressure plasma jets (APPJs)

Abstract

In order to maximize the O concentration generated by the atmospheric pressure plasma jets (APPJs), several different methods of adding O2 additive to working gas have been proposed. However, it is not clear, which method is capable of generating the highest concentration of O atom. In this paper, the concentration of O atoms in an APPJs by adding O2 to (1) the working gas, to (2) the downstream inside the tube, and (3) to the shielding gas is investigated by two-photon absorption laser-induced fluorescence spectrometry. The results clearly demonstrate that the highest O density is achieved when 1.5% of O2 is added to the working gas rather than the other two methods. In other words, the most effective way to generate O atoms is by premixing O2 with the working gas. Further investigation suggests that O atoms are mainly generated around the electrode region, where the electric field is highest. In addition, when O2 is added to the working gas, if in the meantime extra O2 is added to the downstream inside the tube, a significant decrease of O density is observed.

Shielding‐gas‐controlled atmospheric pressure plasma jets: Optical emission, reactive oxygen species, and the effect on cancer cells

“…However, as mentioned above, the density of the ground states does not necessarily correlate to the density of the excited species. Interestingly, Yue et al found that the O concentration can increase even more significantly if O 2 is premixed with the working gas instead of mixed into the shielding gas. The long‐distance ROS are likely due to O 3 , which can be created through O reacting with O 2 .…”

“…The reactive species produced by plasma jets are very sensitive to the environmental gas composition and any evaporation from a liquid target surface . For this reason, there have been a few studies in recent years that use a shielding gas to shroud the plasma jet and help stabilize and control plasma propagation as well as reactive species production . However, so far there is a general lack of data related to helium plasma jets with shielding gas in contact with conductive/nonconductive liquid, such as the spatial distributions of the generated reactive species.…”

Recent Progress in Applications of Non-Thermal Plasma for Water Purification, Bio-Sterilization, and Decontamination

“…Ghimire et al [62,63] discussed the variation of RONS with the gap distance, electrode separation, and plasma propagation length. Yue et al [64] and Lamichhane et al [31] studied the effects of working gas on the concentration of RONS. Similarly, Lim et al [65] and Nguyen et al [66] presented the effects of the applied voltage, frequency, and moisture on atmospheric pressure plasma.…”

“…Plasma electron can disassociate O 2 into atomic O. This mechanism are the main conditions for the occurrence of tree reaction bodies in the formation of O 3 via Equation ( 10) [64]. In this reaction, M represents other molecules inside the reactor, such as N 2 , O 2 , Ar, He, and Ni.…”

Hydrogen Production via Partial Oxidation Reforming of Methane with Gliding Arc Discharge Plasma

“…There are several ways to generate active oxygen species in this air-methane plasma system. [41][42][43][44] The principle pathway of O production is the O 2 dissociation by electron collisions according to Equation 2.…”