板条射频放电产生单重态氧实验研究

Experimental study on singlet delta oxygen production in slab RF discharges

通过考察各种放电状态及气流条件下发生器内外物种的自发辐射谱,发现光谱峰值强度与对应物种浓度成正比。分析了主要的等离子体动力学过程,了解了单重态氧及其它物种的浓度变化规律。考察了α放电和γ放电两种不同的放电方式。发现在α放电状态下,体系中有较少氧原子等淬灭性粒子,更有利于O2(1Δ)产生。加入He,有效地降低了气体体系的离子化阈能和约化场强,约化场强最小时,产生的O2(1Δ)浓度最大,相较于纯氧放电,O2(1Δ)浓度提高一倍以上。考察了腔外各物种浓度的变化,O2(1Δ)离开放电腔后浓度稳定,沿距离减少较慢,有益于出光。优化了本系统的放电极间距,极间距太大或太小,都不利于单重态氧的产生。

This paper reported that the peak intensity values of spectra are in direct ratio with corresponding species＇ concentration values. Major plasma-kinetic processes and concentration varieties of major species with varied flow conditions and discharge forms were researched. Slab RF discharges with gas flow are possible in two greatly different forms that are α discharge and γ discharge. A discharge gives higher O2 （^1△） production for fewer quenching particles. Lower specific field intensity values which are helpful for the O2 （^1△）production can be achieved by adding helium. The peak O2 （^1△）concentration with oxygen and helium mixture gas flow is more than 2 times as high as pure oxygen discharge. O2 （^1△）loss in afterglow region is lower than 50~ in 0.03 s, while stable O2 （^1△） concentration is helpful for lasing. Electrode gap is optimized with 14.5 mm in the singlet delta oxygen production system. Both bigger gaps and smaller gaps go against the production of singlet delta oxygen.