Transformation of Organic Solvents into Carbon-Based Materials by Liquid-Phase Plasmas

Abstract

The possibility of modifying chemical properties of organic liquids under the influence of strong electric fields created by pulsed electrical discharges with energies on the order of J/pulse is quite intriguing. Considering the majority of carbon-based materials today are almost exclusively synthesized from gaseous precursors, the realization of this process even seems necessary. The goal of this study was to examine the possibility of synthesizing carbon materials using streamer-like electrical discharges in three different organic liquids: methanol, acetone and pentane. The morphology of the deposited carbon was imaged using scanning electron microscopy whereas energy dispersive X-ray spectroscopy was used to analyze chemical composition of the resulting films and particles. The results have shown that electrical discharges in all three liquids result in the carbon deposition on the high-voltage electrode. Depending on the type of the organic liquid, the thickness of the carbon layer deposited on the electrode can rise 10–70 % above baseline levels and the deposition is accompanied by a change in surface morphology of the electrode. Electrical discharges in acetone and pentane also result in the deposition of solid carbon particles in the bulk liquid. The mechanism for the formation of solid carbon byproducts was correlated with chemical reactions in plasma.