Effect of an additional floating electrode on radio frequency cross-field atmospheric pressure plasma jet

Atmospheric pressure plasma jets with cross-field electrode configuration are a potential jet design for gases with high breakdown fields. This study focuses on the effect of an additional floating electrode on the cross-field plasma jet properties. Detailed experiments are done with the additional floating electrodes of different widths introduced below the ground electrode in a plasma jet with a cross-field electrode configuration. It is observed that in the presence of an additional floating electrode in the jet propagation path, less applied power is needed for the plasma jet to cross the nozzle and jet length increases. This threshold power, as well as the maximum jet length, depends on the electrode widths. A detailed analysis of charge dynamics in the presence of an additional floating electrode shows decrement in the net charge transferred radially to the external circuit through the ground electrode, and an increment in the net charge transferred axially. Increment in the optical emission intensity of reactive oxygen and nitrogen species, as well as the relative yield of ions like N+, O+ , OH+ , NO+ , O-, and OH- in the plasma plume, that are crucial for biomedical applications suggest an improvement in the reactivity of plasma plume in the presence of additional floating electrode.

Automated summary

This study investigates the effect of an additional floating electrode on the properties of an atmospheric pressure plasma jet with a cross-field electrode configuration. The experiments show that the presence of an additional floating electrode reduces the power required for the plasma jet to cross the nozzle and increases the jet length. The threshold power and maximum jet length depend on the width of the electrode. The analysis also reveals an improvement in the reactivity of the plasma plume due to the increased optical emission intensity and relative yield of ions in the presence of the additional floating electrode.