Modification of thermally reduced graphene oxide by the SF6/Ar plasma treatment

Abstract

The effect of SF₆/Ar plasma on the properties of partially thermally reduced graphene oxide (GO) was studied by Raman spectroscopy, scanning electron microscopy, X-ray energy dispersive spectroscopy, and the current–voltage characteristics. Samples were treated by SF₆/Ar plasma for up to 45 min at the power of 100–250 W. The fluorine content and the resistance of samples depending on the time of treatment were determined. It was established that the fluorine content in GO was more than 20 wt % if the treatment time was 45 min. It was shown that the sharpest change in the resistance occurred during the initial plasma treatment. In the subsequent processing, there was a gradual increase in the resistance, whose value varied slightly during the heat treatment at up to 450°C. No noticeable increase in defects on the surface of graphene oxide after plasma treatment was detected by Raman spectroscopy and electron microscopy. The fluorination in SF₆/Ar plasma was explained by the formation of C–F bonds with the structure of graphene oxide.