Insight into the generation network of reactive oxygen species in H2O under nonthermal atmospheric-pressure plasma irradiation using a kinetic modeling approach

• Developed kinetic model for atmospheric-pressure plasma irradiation. • Used the proposed model to interpret ROS generation networks in H 2 O. • Performed plasma irradiation experiments using H 2 O under various conditions. • Considered the minimum necessary elementary reactions in this model. • Described experimental results under interpolation and extrapolation conditions. A kinetic model incorporating the dominant generation networks of reactive oxygen species (ROS) in H 2 O under nonthermal atmospheric-pressure plasma irradiation was developed in this study. In the proposed model, the minimum necessary elementary reactions involving ROS were considered based on the behaviors of the dissolved O 2 and H 2 O 2 observed in plasma-irradiated H 2 O. The ROS included not only OH radicals but also other ROSs such as OOH, O, and these anionic radicals. The model agrees well with the experimental results for various initial dissolved O 2 concentrations, pH values, and input power conditions. Further, the model could predict specific behavior under extrapolated conditions, which are in the presence of H 2 O 2 at the initial conditions. In addition, the reaction rates of elementary reactions involving dissolved O 2 , which are difficult to measure in the experiments, were simulated by the model. It was found that the reaction rates between the consumption and production reactions of dissolved O 2 were balanced at later stages of nonthermal atmospheric-pressure plasma irradiation. The model is expected to provide fundamental guidelines for the effective utilization of nonthermal atmospheric-pressure plasma irradiation.