Nanostructured Carbon Coatings on Silicon Carbide: Experimental and Theoretical Study

Nanotechnology has been recognized as an emerging technology of the new century. Control over the structure of materials on nanoscale can open opportunities for the development of nanostructured materials with controlled properties, if the structure/property relations are known. This paper describes a technique that can produce a broad range of potentially important carbon nanostructures that may be used in future technologies. Nanostructured carbon coatings can be obtained either by deposition from the gas phase onto a substrate, or by surface treatment of a carbon-containing substrate. The method presented in this paper is accomplished through the extraction of metals from carbides (SiC and TiC) using chlorine or chlorine-hydrogen mixtures. This is a versatile technology because a variety of carbon structures can be obtained on the surface of carbides in the same reactor. Not only simple shapes, but also fibers, powders and components with complex shapes and surface morphologies can be coated. This technology allows the control of coating growth on the atomic level, monolayer by monolayer, with high accuracy and controlled structures.