CARBON NANOPARTICLES BASED ON THERMALLY EXPANDED GRAPHITE: EFFECT OF THE TEG OBTAINING ROUTE ON THE PARTICLES MORPHOLOGY

Abstract

The paper presents the investigation results of the morphology of carbon nanoparticles formed during liquid-phase exfoliation of thermally expanded graphite in tert-butanol. The thermally expanded graphite used in this work was obtained by thermal expansion of graphite nitrate with acetic and formic acids in the thermal shock mode at 500°C and 900°C. Initial cointercalate was shown by powder X-ray diffraction analysis to be the mixture of the II^nd and the IV^th stage intercalation compounds. It has been established by transmission electron microscopy that dispersions of carbon nanoparticles formed during the exfoliation of thermally expanded graphite in tert-butanol via sonication contain mainly few-layer graphenes, the planar dimensions of which reach 8 μm. The influence of the conditions for thermally expanded graphite obtaining on the morphology of resulting carbon nanoparticles is discussed. Dispersions based on thermally expanded graphite obtained at a lower temperature, in addition to few-layer graphenes, also contain a significant amount of amorphous carbon particles with planar sizes up to 100 nm.

Keywords

• few-layer graphenes
• liquid-phase exfoliation
• graphite nitrate
• cointercalation