Reaktionskinetik der Ozonbildung in der Sauerstoffglimmentladung

Abstract

Abstract Hg‐light absorption at λ = 2537 Ǎ by O 3 has been used to measure the concentration of O 3 in the positive column of an oxygen glow discharge under the nonstationary conditions of the Q‐form (tube diameter 3:4 cm). For all gas pressures investigated ( p = 7 — 12 torr) the O 3 density ( n 3 ) as a function of the current reaches a remarkable maximum at i ≈ 15 mA. n 3 max was found to increase almost linearly with the gas pressure. A t i = 80 mA, on the other hand, n 3 increases according to a quadratic relation. In order to understand the dependence of n 3 on the pressure and on the current density (or equivalently on the electron density n e ) a kinetic model previously developed has been used involving the following particles equation image . For example, it can be shown that in the region of the maximum of n 3 one main production process of ozone is the associative detachment reaction equation image . The calculated maximum of the ozone density is higher than the measured one and appears at higher electron density.