Attempt to control chemical reactions in liquid induced by atmospheric-pressure DC glow discharge

Nonthermal atmospheric-pressure plasmas in contact with liquid are widely studied aiming variety of plasma applications. DC glow discharge with liquid electrode is an easy method to obtain simple and stable plasma-liquid interface. When we focus attention on liquid-phase reaction, the discharge system is considered as electrolysis with plasma electrode. The plasma electrode will supply electrons and positive ions to the liquid surface in a different way from the conventional metal electrode. We tried to control the liquid phase reaction in plasma-assisted electrolysis by using the pH buffer solution to fix the pH, and by using the ion exchange membrane. The advantage of ion exchange membrane is not only the control of ion migration but the use of different solutions at anode side and cathode side. The controllability of plasma-assisted electrolysis in this work was evaluated from the temporal change of chemical species in liquid such as NO2- and NO3-, and from the metal nanoparticles generation.