为研究氩气(Ar)添加剂对低温等离子体(NTP)转化NO过程的影响,建立了NTP转化NO/N2/O2/Ar气氛中NO的试验平台,考察了激励电压峰-峰值(Vp-p)和Ar浓度对NO转化率、NO2、O3浓度及发射光谱的影响,并结合发射光谱诊断法对NTP转化NO的机理进行了分析。研究结果表明,Vp-p较小时,由于潘宁效应,在NO/N2/O2气氛中加入Ar会增加分子的活化几率;另外添加Ar会引起NTP电子密度的增加,从而促进N、O原子的生成,NO转化率随Ar浓度升高而升高;Vp-p较高时,混合气加入Ar后会抑制O3的生成,O3浓度随Ar浓度升高而降低;NO2浓度的变化趋势与O3浓度变化相似。
NO conversion in NO/N2/O2/Ar mixtures using non-thermal plasma(NTP) was studied to investigate the impact of Ar on the NO reduction process. The effect of applied voltage(Vp-p) and Ar concentration on NO conversion efficiency, NO2 concentration, O3 concentration and emission spectroscopy were examined. Chemical mechanism of NO conversion was analyzed with emission spectroscopy diagnosis. The obtained results show that adding Ar in the NO/N2/O2 mixture can enhance activation probability of molecules at low Vp-p due to the penning effect. Furthermore, the electron density of NTP increases with Ar, which promotes the formation of N and O atoms. NO conversion efficiency rises with the increasing of Ar concentration. With high Vp-p, Ar has a negative effect on O3 generation, and O3 concentration reduces with the increasing of Ar concentration. The variation of NO2 concentration is similar to that of O3 concentration.