Vapor-air discharges between electrolytic cathode and metal anode at atmospheric pressure

Non-thermal plasmas in and in contact with liquids

“…• a large cathode fall at the water cathode(e.g. [114,[125][126][127][128]), typically higher than for a metal electrode [129]; • the glow discharge structure (for low current discharge) with a water anode consisting of a cathode fall, a negative glow, a Faraday dark space, a positive column and an anode glow [114,130] (see figure 11(e)); • the electrical field is constant in the positive column of the plasma [114,126,127]; • the discharge voltage is independent of the current when corrected for the temperature rise, constriction of the positive column and current dependence of the cathodeanode voltage drop [114]; • the cathode current density is independent of the discharge current at least for low conductive solutions [128,114], although for electrolyte solutions a dependence of the current density on the current is observed [128]; • pattern formation on the water anode which is a typical feature for glow discharges in contact with resistive electrodes [114].…”

“…A phenomenological study of dc-excited electrical discharges between a metal pin and a water electrode is done by Gaisin and Son [127] and Gaisin [131] for currents up to amps. They found that with the increase in the current and the interelectrode distance the discharge becomes more filamentary and also a multiple cathode spot structure emerges.…”

The characterization of radio-frequency discharge using electrolyte solution as one electrode at atmospheric pressure

“…Previous works on the dc-driven plasma-solution system [4][5][6] suggested that the solute atoms observed in the plasma zone originate from the sputtering of positive ions in the plasma. In order to verify this idea in our experiment, we investigated the dependences of the Na I (589 nm) line intensity and the self-bias (on the solution) on the pH value of the solution.…”

“…Since direct current (dc) glow discharge using electrolyte solution as one electrode was initially explored [1], research interests have grown, such as in polluted water detection [2,3], novel materials fabrication [4][5][6] and a new emission source for the direct analysis of the dissolved metal content in aqueous solutions [7][8][9], without using complicated vacuum equipment. In the detection of polluted water, researchers make use of one feature of the plasma-solution system, i.e.…”

“…In order to elucidate the possible solute transport mechanism, considerable efforts have been made. Three typical mechanisms of solute atom transport have been proposed [4][5][6]. Although the detailed processes were different from one another, they were consistent in assuming that sputtering caused by energetic positive ions bombardment was the primary source for solute transport, which was first indicated by Hickling [10], since the cathode potential fall reached around 500 V. Discharges with an electrolyte as one electrode of discharge driven by a dc source have been intensively investigated in experimental and theoretical 1 Author to whom any correspondence should be addressed.…”