Optimizing Copper Electrode for Efficient Plasma Generation Using Microwave System at Atmospheric Pressure

This study investigates the thermal distribution on copper electrodes during plasma generation using microwave irradiation at 2.45 GHz at atmospheric pressure.Copper electrodes of varying lengths (3 cm, 6 cm, and 18 cm) were tested to determine the optimal length for stable plasma generation.A conventional microwave oven, operating at 17%, 33%, and 55% power, was used to generate plasma, while a thermal imaging camera captured the temperature distribution across the electrodes.The results indicate that the 6 cm electrode, corresponding to half the microwave wavelength, produced the most efficient and stable plasma, with temperatures reaching 182C within five minutes at 55% power.In contrast, the 3 cm electrode, representing one-quarter wavelength, failed to generate plasma, showing significantly lower temperature rise.The 18 cm electrode demonstrated intermittent plasma generation and a less stable temperature increase, peaking at 118.4C.These findings confirmed the critical relationship between electrode length and microwave wavelength for optimal plasma generation.The study also observed corrosion on the 6 cm electrode due to prolonged plasma exposure, suggesting further research on corrosion-resistant materials.This work contributes to the understanding of microwave-induced plasma for applications in material processing and waste treatment.