Three-dimensional graphene/polymer composites with exceptional multi-functional properties

3D graphene materials with interconnected networks are prepared using different techniques, including template-based chemical vapor deposition to produce graphene foams (GF) and freeze-drying of graphene hydrogel to produce graphene aerogels (GA). Apart from the intrinsic properties of 2D graphene sheets, these 3D graphene materials possess other unique properties, including extremely low densities, superior electrical conductivities, and excellent elasticity and flexibility. 3D graphene/epoxy composites are prepared by infiltrating epoxy into the porous structure. GF/epoxy composites possess a cellular structure and 3D interconnected graphene network, while GA/epoxy composites possess unusual anisotropic properties due to the layered structure of GA. These composites deliver remarkable electrical conductivities, mechanical properties, and fracture toughness. These observations signify the unrivalled effectiveness of 3D graphene relative to 1D carbon nanotubes or 2D functionalized graphene sheets as reinforcement for polymer composites without the issues of nanofiller dispersion and functionalization prior to incorporation into the polymer.