STUDY OF RF-DBD DISCHARGE IN AR/CH4 MIXTURE IN THE PRESENCE OF NICKEL FOAM AT LOW PRESSURE

This paper investigates the effect of nickel foam on the structure and properties of Radio-Frequency Dielectric Barrier Discharge (RF-DBD) in an Ar/CH4 mixture at a low pressure of 0.5 Torr. Experiments were conducted by varying the supplied power, gas flow, and distance between the catalyst and the RF electrode. It has been shown that an increase in plasma power and a change in CH4 gas flow in the presence of a catalyst leads to a noticeable shortening of the plasma glow length in a quartz tube. It was found that increasing the distance between the catalyst and the RF electrode reduces the ability to maintain plasma in the region downstream of the catalyst. The analysis of optical emission spectra revealed a decrease in the intensity of carbon-containing radicals, atomic and molecular hydrogen after the catalyst, which indicates its active participation in plasma-catalytic processes. Raman analysis confirmed the formation of amorphous carbon deposits on the nickel foam surface. It has been established that nickel foam not only modifies the structure of the RF-DBD discharge, but also significantly affects the distribution of active particles in the plasma, changing the conditions for plasma-catalytic reactions. The results obtained provide a deeper understanding of the mechanisms of interaction between low-temperature plasma and porous metal catalysts and can be used in the development of effective plasma-catalytic systems for the conversion of hydrocarbon gases.

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