München 2019 – wissenschaftliches Programm
P 18.23: Poster
Donnerstag, 21. März 2019, 16:30–18:30, Foyer Audimax
Temporal evolution of the electron density of a nanosecond discharge in destilled water — •Katharina Grosse, Julian Held, and Achim von Keudell — Ruhr-Universität Bochum
Plasmas inside liquids allow a high mass transfer of reactive species from the gas phase into the liquid. Fast and efficient reaction rates for surface reactions can be realised when a surface is in direct contact with the plasma treated liquid. These plasma-liquid systems are relevant for surface modifications as for example plasma enhanced anodisation of metal surfaces inside an electrolyte. The physics of these plasmas and the interaction of the generated species with different surfaces need to be investigated to gain a full understanding of the chemical reactions occuring at the plasma-liquid-surface interface. A 10 ns pulsed plasma with a voltage amplitude of 20 kV at a repetition frequency of 15 Hz is ignited inside destilled water. The temporal evolution of the electron density and temperature is determined from the line broadening of the Hα-line (656 nm) and one OI-line (777 nm), measured with time-resolved optical emission spectroscopy (OES) with a temporal resolution of 15 ns. The electron densities are in the order of 1025 m−3 and electron temperatures between 0.1-20 eV are determined.