Investigation of the interaction between a helium plasma jet and conductive (metal)/non-conductive (dielectric) targets

Abstract

Recent research in plasma biology proved that atmospheric pressure plasma jets (APPJs) have a biocidal effect, making them a promising alternative to traditional antimicrobial treatments. Working gas and voltage waveform are well-known parameters influencing the biocide efficiency. The type of surface targeted by the plasma jet also affects the biocidal capability of the APPJs, the streamer propagation, and the chemistry involved. The aim of this study is to investigate experimentally the effect of the target conductivity on the plasma characteristics: plasma jet propagation and reactive species production. The results show that the propagation mechanism is modified when the plasma interacts with the target. These modifications depend on the conductivity of the target. The results also demonstrate that the generation of reactive oxygen and nitrogen species (RONS) is influenced by the target’s conductivity. This study shows that the assessment of RONS generated by APPJs should be performed as close as possible to the real applications conditions.