Influence of electrode material on hydrogen peroxide generation by DC pinhole discharge

Abstract

In this work, several materials were studied as electrodes in a pinhole configuration of a DC plasma discharge to estimate their effect on the efficiency of the discharge, indicated by hydrogen peroxide production. Detection was carried out using a specific titanium reagent. This was combined with ICP-OES analysis of the final solutions to determine the difference between the amount of electrode material released during the discharge operation and electrolysis experiment carried out under the same conditions. It was found that from seven studied electrode materials, graphite gives the best results, while lower cost aluminum and titanium-zinc still work well. The most unsuitable materials were copper and brass; in these cases, no hydrogen peroxide was detected in the cathode part of the reactor. Results obtained by ICP analysis indicate that even in the case of brass, the absence of hydrogen peroxide is due to the presence of copper in the material. It probably affects both directly the phase of discharge creation and propagation and the decomposition reactions.