The air discharge plasma contains numerous reactive species and is frequently used in the preparation of plasma-activated water (PAW). In this study

ozone (O3) produced by nanosecond pulse dielectric barrier discharge (DBD) was employed to quantitatively oxidize nitrogen oxides (NOx) formed during air DC glow discharge. We investigated the water absorption efficiency of NOx characterized by different N valence states (including NO

NO2

and N2O5) within mixed gases. Furthermore

we evaluated the inactivation effect of the resulting aqueous solutions on Staphylococcus aureus. The results indicate that

by adjusting the ozone concentration generated by DBD in a pure oxygen environment

highly selective gaseous NO2 or N2O5 can be synthesized. Increasing the N valence state in NOx significantly enhances its water absorption efficiency. Once all NOx is oxidized to N2O5

a single water treatment can achieve 100% absorption efficiency

enabling the complete and rapid capture of nitrogen fixation products from air discharge. Additionally

the PAW produced under increased N valence demonstrates decreased pH and significantly elevated conductivity

although the difference in oxidation-reduction potential (ORP) is minimal. The PAW inactivation experiments demonstrate that elevating the N valence in NOx effectively reduces the survival rate of Staphylococcus aureus

with a maximum reduction of 81.8%. Extending the treatment time with PAW can further enhance sterilization efficiency

achieving 100% inactivation of Staphylococcus aureus within 80 minutes. This study offers valuable insights into the rapid absorption of air discharge products and the efficient preparation of PAW.