Graphene 3D architectures

In this chapter, recent progress in the fabrication and characterization of 3D graphene-based structures will be summarized. Although there have reports on this aspect [1, 2], a more extended discussion on each method has been not available, due to the space limitation in most cases. As stated earlier, graphene has attracted much attention, due to its unique structure, together with various extraordinary chemical and physical characteristics [3-5], thus leading to a wide range of potential applications in various fi elds [5, 6]. Due to its zero-gap semi-metal properties, pure graphene cannot be used to develop devices similar to those based on normal semiconductors [7-9]. This is the driving force to develop well-defi ned structures, including nanoribbons [10-12] and quantum dots [13, 14]. More specifi cally, graphene-based materials, which are used in energy, environment and biological applications, require 3D structures [15-18]. The 3D structured graphene materials could have high specifi c surface areas, strong mechanical properties and rapid mass and charge transport kinetics, due to the synergistic effect of the 3D porous structures and the intrinsic high conductivity of graphene. 3D graphene structures have also various other names, such as networks, foams, sponges, hydrogels and aerogels, which will not be specifi cally emphasized in this chapter and just follow the original references.