Pulsed dc- and sine-wave-excited cold atmospheric plasma plumes: A comparative analysis

Abstract

Cold atmospheric-pressure plasma plumes are generated in the ambient air by a single-electrode plasma jet device powered by pulsed dc and ac sine-wave excitation sources. Comprehensive comparisons of the plasma characteristics, including electrical properties, optical emission spectra, gas temperatures, plasma dynamics, and bacterial inactivation ability of the two plasmas are carried out. It is shown that the dc pulse excited plasma features a much larger discharge current and stronger optical emission than the sine-wave excited plasma. The gas temperature in the former discharge remains very close to the room temperature across the entire plume length; the sine-wave driven discharge also shows a uniform temperature profile, which is 20–30 degrees higher than the room temperature. The dc pulse excited plasma also shows a better performance in the inactivation of gram-positive staphylococcus aureus bacteria. These results suggest that the pulsed dc electric field is more effective for the generation of nonequilibrium atmospheric pressure plasma plumes for advanced plasma health care applications.

Possibilities and analytical properties of the radiofrequency plasma pencil operating in the continuous and in the pulsed mode

“…In 30 the first mentioned case an optical emission diagnostics of the plasma is a very frequent approach. Herein the following parameters were measured: Gas temperature (T g ) from Boltzmann plots of rotational lines (Q 1 1-Q 1 9) of OH spectra, excitation temperature (T e ) from a set of argon atomic lines (603.21, 667.73, 35 675.28, 687.13 and 714.70 nm) and electron number density (N e ) from H β line Stark broadening yielded from the fitting the line intensity profile by the Voigt function [25, 27,28]. [3][4][5].…”

“…The continual mode could be changed to the pulsed mode using pulses synchronised with the repeating laser frequency [9]. A pencil-type plasma jet driven by pulsed DC 35 voltage and low-frequency AC voltage was applied to plasmacancer cell interactions [10]. The sine-wave excited plasma causes a lower optical emission and significantly lower discharge current than DC excited plasma features.…”

Comparison of two cold atmospheric pressure plasma jet configurations in argon

“…The plasma parameters and duration of active plasma phase in turn depend on a variety of external parameters: jet configuration, voltage amplitude and waveform, and working gas and its flow rate. There are numerous studies concerning the effect of these external parameters on the electron density and electron temperature, while the effect of the duration of active plasma phase has been investigated less thoroughly.…”

High‐Rate Deposition of Electrochromic Organotungsten Oxide Thin Films for Flexible Electrochromic Devices by Atmospheric Pressure Plasma Jet: The Effect of Substrate Distance

“…Hence, surface processing and film deposition by cold atmospheric plasmas are among the most intensively studied technologies during the last decade, which include: (i) surface pretreatments for cleaning, activation or passivation; (ii) deposition of films; and (iii) post‐treatment on coated surfaces for adjusting the chemical composition or crystallinity of the coating 1. Cold atmospheric plasmas have been tested for plasma medicine applications such as the treatment of living cells2 and sterilization 3. Film deposition regimes in cold atmospheric plasmas are commonly based on plasma‐enhanced chemical vapor deposition (PECVD), which is due to the reactive radical species created in the plasma at atmospheric pressure using high voltages 1.…”