Probing ionization characteristics of under-water plasma arc discharge using simultaneous current and voltage versus time measurement in carbon nanoparticle synthesis

This study investigated the characteristics of plasma ionization that occurs during plasma arc discharge in water using carbon electrodes. The characterization of plasma ionization begins by observing the arc shape using a digital camera associated with voltage oscillation using current and voltage vs. time (I-t and V-t) characteristics. Furthermore, the ionization energy calculation is performed using simultaneous I-t and V-t measurement data. These calculations are then compared to the photon energy from the optical emission spectroscopy (OES). The results from the digital camera indicate four types of arc discharge in terms of shape and intensity related to voltage oscillation. Moreover, the energy calculations show that by using the I-t and V-t methods is possible to measure the plasma ionization detected not only in the range 1-4 eV but also in the outside range, including smaller than 1 eV and greater than 4 eV. These ranges correspond to the emission lines in visible light, infrared, and ultraviolet, respectively. In addition, the I-t and V-t methods can also measure the excitation and recombination energy of the arc discharge plasma ionization. This study reveals the possibility of investigating the characteristics of plasma ionization using simultaneous I-t and V-t measurements, which comprise an easier and more practical method in the diagnostics of carbon nanoparticle synthesis

Automated summary

This study investigates the characteristics of plasma ionization during plasma arc discharge in water using carbon electrodes. The arc shape and voltage oscillation are observed using a digital camera and current and voltage vs. time characteristics. The ionization energy is calculated using simultaneous measurement data and compared with optical emission spectroscopy data. The results show four types of arc discharge and the ability to measure ionization energy within and outside the 1-4 eV range. This study reveals the possibility of using simultaneous measurements to investigate plasma ionization characteristics.