Time-sharing synergy of NO_x mode and O₃ mode air discharges for efficient and pollution-free disinfection

As an alternative disinfection technology, air plasma is limited to achieve wider application due to its restricted disinfection level and hazardous by-products including O₃ and NO_x. In this work, a time-sharing synergy strategy is proposed, where NO and NO₂ are first generated by a dielectric barrier discharge reactor in NO_x mode, and then the discharge is switched into O₃ mode by increasing flowrate, thus producing large amounts of high-valence NO_x for efficient disinfection in sealed space. The disinfection effect of time-sharing synergy is about 2 logs higher than using single O₃ or NO_x mode with the same discharge power. The concentration of high-valence NO_x is highly correlated with disinfection effect. Finally, all disinfection ingredients are removed after 2-min gas-washing and heating.