Enhanced Atmospheric Pressure Plasma Jet Performance by an Alternative Dielectric Barrier Discharge Configuration

A conventional coplanar-coaxial dielectric barrier discharge is operated with two-ring electrodes exposed to the atmosphere; however, this condition can potentially generate sparks between the electrodes. Here, we showed that sparks between the electrodes were avoided by completely covering the electrodes in the electrical insulation. This new configuration provided a high-level performance in generating a plasma jet in comparison with the configuration with the electrodes exposed to the atmosphere, i.e., it provided a stable discharge and long-plasma plume, reduced discharge power, and increased the range of applied voltage. A short distance between the electrodes and the ground electrode led to an extended jet length and a reduced jet temperature. This is a promising plasma jet source for various applications in that excited species are present in the jet and the emission of NO
_x
and CO is low.