Research progress in construction of three-dimensional carbon materials based on sp2 hybridization

sp2 hybridization is one of the most important forms of carbon-carbon bondings, and the threefold symmetry related to the bonding has led to the formation of stable graphite structure and meso-stable structures of fullerenes, carbon nanotubes and graphene. The electrons that are not involved in the hybridization form π bonds with good electric conductivity and other unique electronic properties especially in carbon nanostructures. With exotic physical, chemical and biological properties, sp2 hybridized carbon nanomaterials have attracted great attention and are expected to be applied in the fields of electronics, energy, biomedical, pharmaceutical, functional materials, etc. In the present many studies, the above-mentioned nanomaterials often need to be constructed into three-dimensional materials so as to exhibit the superior characteristics of the nanomaterials on a larger scale. This paper presents a review of the recent advances in three-dimensional materials based on sp2 hybridized carbons, and give comments on the interaction between the building blocks and factors involved in the construction.