A hybrid gas-liquid discharge can effectively improve the concentration and type of active species in solution

which is promising for applications in liquid food sterilization

however

the understanding of the discharge mechanisms and the methods to control the application remains unclear for lack of studies on the characteristics of hybrid gas-liquid discharges. In this study

a parallel dual high-voltage electrode hybrid discharge with a parallel structure generated simultaneously at the gas-liquid interface and in the liquid phase is proposed. The characteristics of hybrid discharge were studied in comparison with the Ar needle-water interface discharge and N2 bubble discharge in terms of electrical

plasma and solution properties. The efficiency of three discharge systems was evaluated with two bacteria

namely

Escherichia coli and Staphylococcus aureus. The results indicate that the hybrid discharge exhibits an intensity between that of the Ar needle-water interface discharge and the N2 bubble discharge. However

the hybrid discharge effectively combines the advantages of interface and bubble discharges

thereby exhibiting a high inactivation efficiency for both bacteria. The treatment is capable of completely inactivating both within 5 min

which is obviously higher than the other two systems. The inactivation of bacteria in the hybrid discharge system is primarily attributable to the ultraviolet(UV) radiation generated by the discharge

the acidic environment

and the ONOOH/ONOO- produced by the reaction between H2O2 and NO2−.