Controlled synthesis of NO in an atmospheric pressure plasma by suppressing NO destruction channels by plasma catalysis

Abstract

NO synthesis using plasma catalysis is analyzed in a parallel-plate atmospheric pressure RF plasma from N2/O2 admixed to helium exposed to Fe and Pt catalysts on a SiO2 support. The NOx species are measured by Fourier-transform infrared spectroscopy in a multi-pass cell. The trends in species densities can be well explained by air chemistry reactions, where NO’s progressive oxidation occurs with increasing oxygen admixture and ozone generation. The sequence can be controlled by the state of the surface that preferentially quenches O3 and allows for an optimum NO production. The maximum production of NO is found at 70% N2/(N2+O2) mixture ratio at 120 ∘C using sandblasted glass, with a conversion rate of 0.085%.