Dynamics of NO, N₂O, and ONOOH in atmospheric-pressure air dielectric barrier discharge: decoupling energy density and gas temperature effects varying with discharge voltage

Abstract

The dose regulation of reactive nitrogen species is crucial for biomedical applications. In this study, we developed a global chemical kinetics model comprising 92 species and 1018 reactions to investigate the regulatory dynamics of three types of reactive nitrogen species, i.e., NO, N2O, and ONOOH, which vary with the discharge voltage in an air coaxial dielectric barrier discharge. Based on the experimental results, the model can describe the density variations of NO, N2O, and ONOOH. The simulation results indicate that the O, NO3 - , NO2 - , and O3 are essential intermediate species related to NO generation; N, NO2, O-, N2 *, and O(1D) are essential intermediate species related to N2O generation; and O2 -, NO, NO2, OH, O4 -, and O3 are essential intermediate species related to ONOOH generation. The individual and comprehensive effects of the energy density and gas temperature on the density of NO, N2O, and ONOOH and the corresponding intermediate species are quantified under increasing discharge voltages. The simulation results indicate that the energy density is the primary factor affecting the number density of NO, N2O, and ONOOH, whereas the gas temperature exerts a completely different effect on these three species. These insights are valuable for plasma applications in biomedicine, where the selective and controlled production of reactive nitrogen species is the key for achieving the desired plasma performance.