Contamination in Dielectric Barrier Discharge Plasmas by Electrode Erosion

Dielectric barrier discharge plasmas find applications in various fields, including material synthesis and functionalization, plasma catalysis for gas conversion, pollution control, and biological sample treatment. While electrode erosion in these systems has been observed previously, its full implications have remained unclear. In this study, we analyze the effects of electrode erosion by examining alumina spheres exposed to the plasma using electron microscopy for detailed characterization. Our findings show that electrode erosion leads to the deposition of microscopic particles on the materials inside the plasma reactor. Whereas the operating parameters influence the properties of these particles, their formation and deposition is persistent. These electrode particles are an evident source of contamination and may lead to impurities in synthesized materials or altered plasma discharges after long-term operation. Our study highlights the importance of acknowledging the presence and potential impact of these particles for various DBD plasma applications and calls for greater awareness in the scientific community regarding this source of contamination that has been overlooked so far.