How to produce an NOx- instead of Ox-based chemistry with a cold atmospheric plasma jet

A novel method is presented, which allows to generate a nitrogen oxides (NOx)-dominated chemistry with a cold atmospheric plasma (CAP) jet which typically produces an oxygen-based reactive species (Ox) cocktail. The reactive oxygen and nitrogen (RONS) production of the CAP jet kinpen is monitored using Fourier transform infrared (FTIR) absorption spectroscopy. While in previous approaches, the plasma chemistry of CAP jets operated with noble gases has been influenced with molecular feed gas admixtures of O2 and N2, humidified feed gas, and shielding gas, these methods are now combined in order to obtain a previously unattainable range of operating regimes: The plasma chemistry can be tuned continuously from Ox to NOx dominated, while the degree of oxidation of the produced NOx can easily be influenced.