Investigation of atmospheric pressure dielectric barrier glow discharge in argon/ammonia mixture

In this paper, the influence of ammonia admixture on argon discharge properties is investigated. Electrical measurements, as well as ten-nanoseconds-exposure photographs taken by an intensified charge-coupled device (ICCD) camera, are employed to confirm the existence of atmospheric pressure glow discharge (APGD) in Ar/NH₃ mixture. The breakdown voltage and transition voltage between APGD and filamentary discharge are studied at various ammonia concentrations. The results show that a small amount of NH₃ can lead to APGD due to the Penning ionization of NH₃ molecules by metastable argon, and the breakdown voltage increases with the growth in NH₃ concentrations owing to the electronegative feature of NH₃. The optical emission spectrum of Ar/NH₃ APGD is analyzed. Besides, gas temperature is estimated at 327 K by the diagnoses of the OH (A-X) (0, 0) band of the spectrum.