Microstructures of carbon nanofilaments growing on graphite nanosheets

This study examines microstructures of a special three-dimensional nanocarbon composed of carbon nanotubes (CNTs) and graphite nanosheets (GNSs). The GNSs were made by exfoliating natural graphite flakes, and CNTs were grown on the GNSs by chemical vapour deposition. Nickel nanoparticles were deposited on the GNSs and employed as the catalyst for CNT growth. The micrographs show that initial deposition of carbon atoms results in structures different from the hollow, multi-walled CNTs. This initial portion forms the root of the CNT and becomes the link between the GNS and the CNT. The root is a form of carbon nanofibres (CNFs) with relatively random graphitic structures. After the CNF, CNT and amorphous carbon are followed. The focus here is how the graphitic structure changes from a disordered CNF to a regularly multi-walled CNT.