Investigation of underwater discharge characteristics and sterilization efficiency of a dual-dielectric plate–air gap device

Abstract In recent years, cold atmospheric plasma has witnessed rapid development and exhibited excellent performance in inactivating pathogenic microorganisms. Here, we design a dual-dielectric plate–air gap device that can be inserted directly into water for discharge and investigate its discharge characteristics. Additionally, the effects of voltage, treatment time, frequency and gas flow on the physicochemical properties of plasma-activated water and sterilization efficiency are discussed. Combined transcriptome analysis reveals that the bactericidal mechanism of the dual-dielectric plate–air gap device involves the impact of active nitrogen species on nitrate/nitrite transporters and nitrogen metabolism pathways. Meanwhile, the sterilization efficiency of this device can reach more than 90%.