Experimental research of pulsed discharge in oxygen mixtures

Abstract

The pulsed discharge in oxygen and its mixtures to produce singlet delta oxygen has been studied experimentally at gas pressure of 30~ 936mBar. As singlet sigma state of oxygen O 2 (b 1 Σ g + ) and atomic oxygen O have great influence on the yield of singlet delta oxygen O 2 (a 1 u g ), the visible spectrum of O 2 (b 1 Σ g + ) at 762nm and O at 778nm have been measured, and the effects of argon, helium and carbon monoxide have been discussed. The electric stability was better in O 2 -He than in O 2 -Ar mixtures, while it could be increased quickly with a small amount of CO. In O 2 -He mixtures more oxygen were decomposed than in O 2 -Ar mixtures, while adding CO the decomposition was reduced, the amount of atomic oxygen was decreased, and the O 2 (b 1 Σ g + ) was increased comparatively. The time-resolved spectrum of the plasma has also been measured. The life-time of atomic oxygen was longer than O 2 (b 1 Σ g + )'s, and it could be shorten with argon.