Nickel Catalyzed Growth of Carbon Nanotubes at 873 K

Carbon nanotubes (CNs) have a wide variety of important properties and many potential applications. There are mainly two methods to prepare CNs, one of them is the arc-discharge evaporation, the other is the catalytic decomposition of hydrocarbon. Here we report the preparation of CNs by nickel catalyzed decomposition of methane at 873 K. The CNs formed have the length of several micron, their outer diameters are 30-12 nm, and the inner ones 10-8 nm. The reduction temperature of the nickel catalyst used has significant effect on the amount of CNs formed. It is possible to prepare CNs on a large scale under the relatively mild conditions by the catalytic method.