Effect of rare earth doped electrode on DBD discharge characteristics and methyl violet decolorization

This study investigates the selection of electrode materials in dielectric barrier discharge (DBD) plasma technology and their effect on pollutant degradation efficiency. Specifically, it compares the discharge characteristics and methyl violet decolorization performance of rare-earth copper rod electrodes and pure copper rod electrodes. By analyzing electrical properties, optical characteristics, and decolorization outcomes, the results reveal that the rare-earth copper rod electrode produced more discharge current pulses under identical conditions, with peak discharge current and discharge power increasing by about 5%. Moreover, discharge power significantly increased with higher input voltage. Emission spectroscopy analysis showed that the rare-earth copper rod electrode generated more excited-state particles. In air, the spectral lines were primarily from the second positive band system of nitrogen molecules N₂(C³П−B³П) below 400 nm, while in oxygen, a broader range of excited-state particles was observed, mainly from a series of oxygen atomic emission lines and characteristic lines of oxygen. Methyl violet decolorization tests demonstrated that both electrodes achieved over 96% decolorization within 2 minutes. However, the rare-earth copper rod electrode enhanced decolorization efficiency by approximately 4%, owing to its superior thermal stability and conductivity. Additionally, its corrosion resistance makes it more suitable for use in corrosive environments such as water treatment. These findings highlight the significant advantages of rare-earth copper rod electrodes in improving discharge efficiency and pollutant degradation, offering valuable insights for optimizing electrode materials in DBD plasma technology.