Oxides yield comparison between DBD and APPJ in water-gas mixture

Abstract

The reactions have been accompanied ultraviolet (UV) radiation and electron impact with discharge plasmas in water-gas mixture, which can generate oxides such as ozone (O3), hydrogen peroxide (H2O2) and nitrogen oxides (NOx). Two plasma processing systems were established by means of a dielectric barrier discharge (DBD) arrays in water mist spray and an atmospheric pressure plasma jet (APPJ) immersed water 1 2. The yield characteristics of oxides in treated water were compared between the APPJ and DBD system under different control parameters. The results show that the relative intensity of UV from both the APPJ and DBD in water-gas mixture are stronger than the ones in air. The concentrations of O3 and NOx in treated water increased with increasing treatment time by using of both APPJ and DBD. Meanwhile, the APPJ treated water is more acid than the DBD treated one. However, it does not exist H2O2 in APPJ treated water, rather it is enhanced in DBD treated water with increasing discharge time. Moreover, the yields of produced oxides in water with discharge in water-gas mixture increased with increasing input power, and decreased with decreasing discharge voltage. This work clearly demonstrates the close coupling of the yields of oxides and discharge voltage, and thus is helpful in the study of the mechanism and application of discharge in water-gas mixture.