Growing carbon nanotubes on graphite
The processing and the resulting microstructures of carbon nanotubes (CNTs) grown on graphite nanosheets (GNSs) is examined. The GNSs have a planar shape and are 20-50-nm in thickness. The GNSs were made by the intercalation and exfoliation of natural graphite flakes. Nickel particles serving as the catalyst were distributed on the GNSs. A chemical vapour deposition (CVD) method was used to grow CNTs. Both methane and acetylene were used as the hydrocarbon gases, and the reaction temperatures studied were 700 and 900°C. The distribution of the nickel particles was found critical for the growth of the resulting nano-carbon filaments. Both CNTs and carbon nanofibres (CNFs) were obtained. The nanocarbon filaments vary widely in density, shape and microstructures, dependent on the processing conditions. The microstructure of the joint between the CNT and GNS has been observed by electron microscopy.