Ultrahigh-Speed Synthesis of Nanographene Using Alcohol In-Liquid Plasma

Ultrahigh-speed synthesis of high-crystallinity nanographene was realized using an alcohol in-liquid plasma, which was generated from a nonequilibrium microhollow atmospheric-pressure plasma with an ultrahigh electron density. The synthesis rates of carbon materials were 0.61 and 1.72 mg/min using ethanol and butanol, respectively. Multilayer nanographene structures obtained using ethanol had an interlayer spacing of 0.33 nm, corresponding to that of (002) planes in graphite. The G-, D-, D'-, and 2D-band peaks in the Raman spectrum also confirmed the formation of nanographene. The mechanism of gradual growth of six-membered ring structures was clarified by gas chromatography of the filtrate.