Gliding arc discharge |
A gas/water mixture flows between two diverging electrodes |
Improved sequestration of volatile reactants such as H2O2; continuous flow |
Low liquid flow; more complex system; difficult to scale |
Dielectric barrier discharge |
Plasma discharges from an internal electrode through a porous dielectric barrier and into a gas/water mix |
Exposes liquid to reactive species more effectively than point/plane-to-plane approaches; can be continuous flow; some scale-up potential |
More complicated apparatus; higher power usage; lower liquid flow |
Surface-water point-to-plane |
Pointed electrode at high voltage above solution with a grounded plane electrode in solution |
Simpler system that does not require as much power as direct discharges; easy to generate plasma; air as an electrode insulator |
Plasma generated species only have contact with the surface of the solution; difficult to scale |
Direct discharge without feed gas injection |
Usually point-to-plane, with a vapor layer (formed at a certain voltage) coating electrode |
Less complex system; feed gas or special electrodes not required; plasma-generated species have direct contact with solution |
Joule heating required to produce vapor around electrodes for discharge facilitation; heavy electrode wear |
Direct discharge with feed gas injection |
Usually point-to-plane with special electrodes at high voltage that release gas to facilitate plasma |
Bubbles enable better tuning of chemistry via feed gas and enhance diffusion of plasma into solution; Joule heating not required to induce vapor around electrode; can be modified into a continuous flow system |
Extensive electrode wear; possible quenching of plasma from liquid |