No/VOL: 09/2022 Page no. 122
Authors: Sergii Bespalko , Jerzy Mizeraczyk :
Title: The plasma discharges in the anodic and cathodic regimes of plasma driven solution electrolysis for hydrogen production
Abstract: This paper presents results of the experimental study of the plasma discharges in the anodic and cathodic regimes of plasma-driven solution electrolysis (PDSE) in 10 wt% Na2CO3 aqueous solution. The study revealed features of the plasma discharge formation at the smaller electrode and values of the breakdown and discharge onset voltages for the anodic and cathodic regimes of PDSE. By applying the fast Fourier transformation analysis, the frequency characteristics of both plasma discharges were found. In the anodic regime of PDSE, the electrical discharge occurred at much higher frequencies (dozens of kHz), while in the cathodic regime at much lower frequencies (hundreds of Hz) but at higher amplitudes of the discharge current and voltage, resulting in higher electrical power dissipation. The applied optical emission spectroscopy (OES) showed emission lines of the hydroxyl (OH*), hydrogen (H*), and oxygen (O*) radicals formed as a result of the dissociation of the water molecules. The obtained results were discussed in terms of the hydrogen production efficiency by the PDSE method.
Key words: plasma electrolysis of solutions, plasma discharges in liquids, discharge frequency characteristics, emission lines, radicals, hydrogen production