Pulsed Discharges for Water Activation and Plasma-Activated Water Production

Discharge plasma interacting with water or aqueous media uniquely loads and delivers external energy and reactive gaseous species to activate water and thus harvests a product, normally termed plasma-activated water/media (PAW/PAM). PAW, with broad-spectrum biochemical activities due to the rich assortment of reactive oxygen and nitrogen species (RONS), holds a promising potential for a range of applications in fields ranging from biomedicine to agriculture. In order to effectively generate and control reactive chemical species in PAW, various power source technologies, reactor and process designs, and many other innovations have been developed to further improve existing PAW production and applications. This chapter presents the current state-of-the-art of using pulsed discharges for the regulation and enhancement of reactive species generated in PAW, and recent advances in understanding the formation pathways, and physiochemical processes of plasma species during plasma-liquid activation, followed by brief discussions of PAW actions in typical applications, including microbial and virus inactivation, cancer treatment, seed germination and plant growth, dentistry and wound healing. Overall, this chapter will provide insights into the efficient production of reactive species in PAW to meet the requirements of different PAW-based applications.