Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
791967 | Journal of Materials Processing Technology | 2006 | 12 Pages |
Carbide derived carbon (CDC) produced by etching SiC in halogens has been investigated using transmission electron microscopy (TEM). Depending on experimental conditions, CDC may contain sp3- or sp2-bonded carbon phases. Amorphous carbon, poorly ordered turbostratic carbon with lattice spacing exceeding values of 0.35 nm as well as highly ordered graphite were observed. sp3-Bonded structures consist of mainly lonsdaleite and cubic diamond nanocrystals. Hexagonal diamond polytypes and n-diamond have been synthesized. During the annealing process, diamond nanocrystals eventually transform to sp2-bonded carbons. The transformation process of hexagonal diamond nanocrystals produces spherical onion type structures. These structures appear either hollow or dense. The latter shows a decrease in lattice spacing compared to d/n values for graphite. Graphitic structures include multi-wall nanotubes, polyhedral particles and ribbons. The graphitization during chlorination of samples may eventually lead to the formation of planar graphite.