Fullerenes, Carbon Nanotubes, and Graphene

We have seen that elemental carbon is quite versatile. In its sp -hybridized solid-state form, it is diamond in its sp -hybridized solid-state form, it is graphite. Over the past three decades, scientists have discovered that sp -hybridized carbon can also form discrete molecules, one-dimensional tubes, and two-dimensional sheets. Each of these forms of carbon shows very interesting properties. 

Because C50 clusters were so preferentially formed, the group proposed a radically different form of carbon, namely, nearly spherical CgQ molecules. They proposed that the carbon atoms of Cgo form a ball with 32 faces, 12 of them pentagons and 20 hexagons ( FIGURE 12.47), exactly like a soccer ball. The shape of this molecule is reminiscent of the geodesic dome invented by the U.S. engineer and philosopher R. Buckminster Fuller, so Cgo was whimsically named buckminsterfullerene, or buckyball for short. Since the discovery of C q, other related molecules of carbon atoms have been discovered. These molecules are now known as fullerenes. 

The two-dimensional form of carbon, graphene, is the most recent low-dimensional form of carbon to be experimentally isolated and studied. Although its properties had been the subject of theoretical predictions for over 60 years, it was not until 2004 that 

How many bonds does each carbon atom in Ceo make Based on this observation would you expect the bonding in Ceo to be more like that in diamond or that in graphite  

Ceo- The molecule has a highly symmetric structure in which the 60 caitxin atoms sit at the vertices of a tmrx ed icosahedron. The bottom view shows only the bonds between cenbon atoms. 

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Nanocarbon structures such as fullerenes, carbon nanotubes and graphene, are characterized by their weak interphase interaction with host matrices (polymer, ceramic, metals) when fabricating composites [99,100]. In addition to their characteristic high surface area and high chemical inertness, this fact turns these carbon nanostructures into materials that are very difficult to disperse in a given matrix. However, uniform dispersion and improved nanotube/matrix interactions are necessary to increase the mechanical, physical and chemical properties as well as biocompatibility of the composites [101,102]. 

Fullerenes, Carbon Nanotubes, and Graphene for Molecular Electronics... 

The purpose of this review is to present recent developments on the utilization of fullerenes, carbon nanotubes, and graphene in molecular electronics. 

We learn how the physical and chemical properties of materials change when their crystals become very small. These effects begin to occur when materials have sizes on the order of 1-100 nm. We explore lower-dimensional forms of carbon— fullerenes, carbon nanotubes, and graphene. 

We have seen that carbon exists in several allotropic crystalline forms graphite, diamond, fullerenes, carbon nanotubes, and graphene. Fullerenes, nanotubes, and graphene are discussed in Chapter 12 here we focus on graphite and diamond. 

Carbon-based nanomaterials fullerenes, carbon nanotubes, and graphene... 

Surface modification of nanomaterials has been the subject of much interest in recent years [180]. Some of these modifications have been performed by diazonium chemistry and include nanoparticles, nanodiamonds, fullerene, carbon nanotubes, and graphene (Table 3.7). 

Although the traditional ceramics discussed previously account for the bulk of production, the development of new and what are termed advanced ceramics has begun and will continue to establish a prominent niche in advanced technologies. In particular, electrical, magnetic, and optical properties and property combinations unique to ceramics have been exploited in a host of new products some of these are discussed in Chapters 18, 20, and 21. Advanced ceramics include materials used in microelectromechanical systems as well as the nanocarbons (fullerenes, carbon nanotubes, and graphene). These are discussed next. 

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