ABSTRACT
Both planar graphite1 and carbon nanotubes2 have been extensively studied, and their structure and properties are well documented in the literature. This section is a review of the current understanding of some less-common nonplanar graphitic materials, such as graphite whiskers, cones, and polygonized carbon nanotubes (graphite polyhedral crystals [GPCs]). Although nonplanar graphitic microstructures in the shape of cones were reported as early as 1957,3,4 it is only recently5-8 that attention has been paid to these exotic classes of graphitic materials. There is no doubt that this growing interest has been triggered by the discovery of fullerenes9 and nanotubes,2,10 which has stimulated intensive research on carbonaceous nanomaterials during the past 25-30 years. Although fullerenes and nanotubes have been discussed in several books during the past decade, carbon cones, whiskers, and other similar structures have received much less attention. Here, our intention is to provide an overview of the current understanding of their structure, synthesis methods, properties, and potential applications.
