Preparation, Structures and Properties of Three-Dimensional Graphene-Based Materials

As a novel two-dimensional carbon nano-material, graphene has the structure of hexagonally-packed single-layer carbon atoms as well as outstanding electrical, chemical, mechanical and thermal properties. However, due to the existence of strong pi-pi bond and van der Waals force between adjacent graphene sheets, graphene are easily agglomerated or re-stacked, therefore greatly reducing their specific surface area and seriously degrading corresponding properties. To date, one of the most effective strategies to address the above problems is to build three-dimensional porous graphene-based materials, thereby not only retaining the intrinsic properties of graphene such as excellent electrical and mechanical properties but also acquiring the advantages of low density, high porosity and large specific surface area. As a result, three-dimensional graphene-based materials have been widely used in versatile functional application fields such as adsorbent, catalyst carrier, biosensor, battery as well as supercapacitor electrode materials. Therefore, the development of the preparation technology of three-dimensional graphene-based materials has attracted great attention. The existing preparation methodologies of three-dimensional graphene-based materials, including self-assembling (hydrothermal reduction, chemical reduction and freeze-drying), templating (colloid template, template-assisted chemical vapor deposition and template-assisted hydrothermal reduction), and 3D printing (direct inking writing, inkjet printing, fused deposition modeling, stereolithography, selective laser sintering/melting) are reviewed. Their advantages as well as disadvantages and forcasts the promising development direction of the preparation technology for three-dimensional graphene-based materials are also summarized.