Comparison of two cold atmospheric pressure plasma jet configurations in argon

Abstract

The present study compares the operation of two cold atmospheric plasma jet (CAPJ) configurations: needle‐to‐cylinder electrode configuration (CAPJ I) and single high‐voltage cylinder electrode around the quartz tube (CAPJ II). The CAPJs were operated in argon flowing through a quartz capillary with 0.5‐mm inner diameter into the ambient air, and the plasma was generated by sinusoidal kHz frequency AC power supplies. The main emphasis of the study was on the mechanism of the initiation of ionization waves for these two configurations. For both CAPJs, there appeared several ionization waves during one half‐period of the applied voltage waveform, and the number of ionization waves increased at higher voltage amplitudes. However, we discovered marked differences in the initiation of the ionization waves for two different CAPJ configuration. The applied voltage controlled the initiation of consecutive ionization waves, which propagated from the grounded electrode towards the tube orifice in CAPJ I. In the case of CAPJ II, certain time had to pass for the initiation of a new ionization wave, and subsequent ionization waves within the same half‐period started at the tube orifice. In addition to the differences in the initiation of the ionization waves, we observed that the CAPJ I was ignited and sustained at lower voltages, while CAPJ II produced a longer plasma jet. The observed advantages and deficiencies of investigated CAPJ configurations point out their potential in different applications.

The production of reactive chlorine species (RCS) by argon and helium plasma jets and the sensitivity of liver cancer cell HepG2 to RCS and H2O2 treatment

“…A larger yield of RCS produced by an Ar/1% O 2 plasma jet was found in a study in which a needle‐to‐cylinder electrode configuration was used. [ 26 ] Besides, the larger the O 2 concentration in the feed gas, the higher RCS production rate could be due to the shorter plasma jet in this type of electrode configuration, [ 53 ] which enables to avoid the production of H 2 O 2 .…”

Application of Y–ZrO2 microtubes as dielectric barrier material in a He atmospheric pressure micro-plasma jet

“…1b. The set-up is similar to the one in our previous studies used for the characterization of quartz tubes [41][42][43][44][45]. Plasma was ignited by a constant frequency (6 kHz) sinusoidal voltage applied to the platinum electrode.…”

“…In the measurements, the resolution of the oscilloscope was 100 ns/div (2 ns per data point) which was taken as the uncertainty. The propagation velocity of the ionization wave was calculated from the time delay between the onsets of current pulse and optical emission pulse in different positions along the tube axis similarly as in our previous work [43][44][45]. Time delay (10 ns) caused by different lengths of cables used for electrical and PMT signal transmission to oscilloscope was accounted for.…”

Micromachining of polymers using atmospheric pressure inductively coupled helium plasma localized by a scanning nanopipette probe microscope

“…Atmospheric pressure plasmas (APPs) have attracted the attention of scientists in various fields such as physics [1][2][3][4][5], engineering [6][7][8][9][10][11][12], medicine [13,14], and biology [15][16][17][18] * Author to whom any correspondence should be addressed. because they are easily generated under atmospheric pressure.…”