Non-thermal plasma, also called cold atmospheric plasma (CAP), is a partially ionized gas in which the electrons carry much higher energy than the bulk gas molecules, so the gas as a whole remains near room temperature. It is the discharge used to produce Plasma-Activated Water (PAW), the subject of the source dossier recorded at Plasma-Activated Water: A source Dossier (Provisional Record).
Distinguishing feature
In a thermal plasma the electrons and the heavy particles are in approximate thermal equilibrium, so the gas is hot. In a non-thermal plasma the two populations are out of equilibrium: energetic electrons drive ionization, dissociation and excitation while the neutral gas stays cool enough to touch a liquid surface or living tissue. This is what makes CAP usable for treating heat-sensitive targets, including water.
Generation
CAP is generated by electrical discharge — for example dielectric-barrier discharge, corona discharge, or plasma jets — in which an applied voltage sustains ionization in a gas stream. The electrical basis links the topic to electricity and physics; the resulting gas-phase chemistry links it to chemistry.
Role in plasma-activated water
When CAP contacts water, the reactive species it generates cross into the liquid, producing the RONS pool, pH shift and redox change characteristic of plasma-activated water. The species family is described on Reactive Oxygen and Nitrogen Species (RONS).
Evidence status
This page describes the general physical character of non-thermal plasma. It does not report any device specification or performance figure from the source dossier, whose ingested capture is incomplete and supplies no such detail.
Related
- Plasma-Activated Water (PAW) — the liquid treatment produced by CAP.
- Reactive Oxygen and Nitrogen Species (RONS) — the chemistry CAP delivers into water.
- electricity, physics, chemistry — broad subject guides.
Source notes & attribution
- https://rexresearch.com/PlasmaActivatedWater/PlasmaActivatedWater.html