Reaction Kinetics and Chemical Quasi‐Equilibria of the Ozone Synthesis in Oxygen DC Discharges

Abstract

Abstract The spatial distribution of ozone and of oxygen atoms was studied along the active and the passive zone of a dc discharge (positive column, pressure: p = (4 … 10) · 10 2 Pa, current: I = 2 … 50 mA, flow rate: F = 5 … 100 sccm) in flowing oxygen. The composition of the final output O 2 / O 3 ‐mixture is controlled by relaxation processes in the passive reactor zone. It is affected sensitively by the total number density and the gas temperature in the afterglow. Steady states meaning reversible chemical quasi‐equilibria were observed and analysed extensively. Within a detailed kinetic model the formation of these equilibria can be explained quantitatively. The synthesis to ozone is controlled above all by the metastable O 2 ( a 1 Δg) species, which modify drastically the results for the basic mechanism, considering the O atoms in the 3 P and 1 D states.