Nanosecond pulsed plasma discharge over a flowing water film: Characterization of hydrodynamics, electrical, and plasma properties and their effect on hydrogen peroxide generation

A continuously flowing liquid film reactor driven by a variable nanosecond pulsed power supply, where plasma channels generated in argon propagate along the water film, was utilized to assess the effects of output voltage setting, pulse frequency, and gas/liquid flow rate on the generation of H2O2. Increasing the voltage significantly impacted the discharge current, resulting in hotter/denser plasma channels that increased the production rate of hydrogen peroxide but lowered the energy yield. Variation in pulse frequency and gas/liquid flow rates had little impact on electrical and plasma properties, however, the production of H2O2 per pulse decreased with increasing pulse frequency and was shown to be linked to insufficient chemical and/or thermal dissipation of the gas phase between pulses. Analysis of a nanosecond pulsed gas discharge propagating across a flowing gas/liquid interface demonstrates the effects of the electrical pulse properties on the resulting plasma discharge properties (plasma temperature and volume, electron density, and temperature) and hydrogen peroxide generation. Hydrodynamic analysis of the two‐phase flow is also presented.