An Ionization-Driven Air Plasma Jet

Abstract

Non-thermal atmospheric pressure plasma jets (NAPPJs) using ambient air as the inducer are of particular and desirable interest but with significant challenges. In this study, we report an air APPJ driven by ionization in the afterglow region, resembling noble gas APPJs. A pin-to-nozzle electrode is used for the air plasma jet with a nanosecond-pulsed DC high voltage as the power supply. Results show that the nozzle diameter plays an essential role in forming the air plasma jet. When the nozzle diameter is 3 mm, the air APPJ is driven by ionization in the afterglow region which is proved by the following three phenomena. First, with an exposure time of 0.1 s, an obvious shiny line (the narrow channel plasma) formed by electron accumulation is observed in the jet. The narrow channel becomes much brighter with a grounding pin approaching the nozzle vertically. In comparison, there is no such phenomenon with a 1-mm diameter nozzle. Second, the afterglow region discharge current of the ionization-driven processes is hundreds of mA distinguished from airflow-driven processes, the afterglow region current of which is typically zero. By using E-FISH to measure the electric field in the afterglow region, it can detect the electric field which has a maximum value of 10.5 kV/cm. Third, the intensity of the N2+ band is much stronger with a 3-mm diameter nozzle than with a 1-mm diameter nozzle, indicating that the local electric field plays an important role in the discharge. We expect this study can offer useful guidelines on the design and understanding of ionization-driven air plasma jets.

Effect of the Atmospheric Plasma Treatment Parameters on the Surface and Mechanical Properties of Carbon Fabric

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Influence of the pulse polarity on micro-hollow cathode helium plasma jet

“…Atmospheric pressure plasma jet (APPJ) is a low-temperature non-equilibrium plasma generated in an open environment outside the discharge region, which has broad application prospects in material processing, nanomaterial growth, biomedicine, and so on [1][2][3][4][5]. During the last decade, the APPJ has become a highlight topic pursued in the field of lowtemperature plasma.…”

Evaluation of Pulsed Spark Discharge for Triggering GaAs Photoconductive Semiconductor Switches

“…Over the past couple of decades, there has been a rapid increase in the research of atmospheric pressure gas discharges. Compared with low-pressure or vacuum gas discharge systems, atmospheric-pressure gas discharge systems have a wide range of applications in scientific, industrial, and medical areas, considering their virtues such as lower costs, portability, and simplicity of operation [13][14][15].…”