In situ processing of electrically conducting graphene/SiC nanocomposites

The outstanding electronic and physico-chemical properties of graphene make it an ideal filler in the fabrication of conducting and robust ceramic composites. In this study, a novel single-step approach for processing electrically conducting and well dispersed graphene/SiC nanocomposites is shown. These materials were processed by growing epitaxial graphene with either α- or β-phase SiC ceramics during their densification via spark plasma sintering (SPS). About 4 vol.% of few-layer graphene domains were generated in situ during the SPS process, leading to a conducting graphene network that significantly enhanced the electrical performance of SiC. The in situ graphene SPS growth mechanism arose from the combined action of the electric current, high temperature and partial vacuum. This approach offers unprecedented opportunities for the fast manufacturing of graphene/SiC nanocomposites with superior electrical and mechanical properties, precluding the handling of potentially hazardous nanostructures. This method widens their possible applications, including micro-electromechanical systems, brakes, micro-turbines or micro-rotors.