Carbon nanoribbons

CNTs (Oberlin and Endo, 1976 Wiles and Abrahamson, 1978 lijima, 1991 Kavan et al., 2001 Yang et al., 2005) and carbon nanoribbons (CNRs) (Novoselov et al., 2004) are graphene-type nanostructured materials having in common a fiber-type structure (Figure 7.4). In CNTs, s T-hybridized carbon atoms are arranged in graphite-type sheets building up seamless hollow tubes capped by fullerene-type (yide infrd) hemispheres. 

Figure 8.4 TEM images of carbon nanostructures grown on carbon nanofibers. (A) Short carbon nanotubes, (B) densely packed carbon nanotubes, fC) carbon nanoribbons, and (D) Y-shaped carbon nanotubes. From Ref. 225, lOP Publishing. Reproduced by permission of lOP Publishing. All rights reserved.

Lu J, Yang J-x, Wang J, Lim A, Wang S, Loh KP (2009) One-pot synthesis of fluorescent carbon nanoribbons, nanoparticles, and graphene by the exfoliation of graphite in ionic liquids. ACS Nano 3 2367-2375... 

Ezawa, M. (2006). Peculiar width dependence of the electronic properties of carbon nanoribbons. Physical Review B, 73, 045432. 

Carbon nanoribbons have also interesting mechanical properties. For instance, Raman spectra show a remarkable dependence on ribbon width (W) (Zhou and Dong 2008). For the... 

Zhou, J., 8c Dong, J. (2008). Radial breathing-like mode of wide carbon nanoribbon. Physics Letters A. doi 10.1016/j.physleta.2008.10.059. 

S.S. Yu, W.T. Zheng, Q.B. Wen, Q. Jiang, First principle calculations of the electronic properties of nitrogen-doped carbon nanoribbons with zigzag edges. Carbon 46(3), 537-543 (2008)... 

The field of carbon nanostructure research is vast and novel, and it experienced a major breakthrough after the discovery of fullerenes in 1985 [1], and their subsequent bulk synthesis in 1990 [2]. This event opened the minds of various scientists towards discovering novel carbon allotropes. Promptly, yet another allotrop of carbon was observed by Iijima [3], although it had previously been produced by M. Endo et al. in the 1970s by chemical vapor deposition (CVD) [4]. The most recent important advance in the quest for novel forms of carbon constitutes the isolation of graphene layers [5], which exhibit unique and exceptional electrical properties [6]. In addition, graphene nanoribbons have recently been synthesized and produced using diverse methods [7]. 

A. Chuvilin, E. Bichoutskaia, M. C. Gimenez-Lopez, T. W. Chamberlain, G. A. Ranee, N. Kuganathan, J. Biskupek, U. Kaiser, A. N. Khlobystov, Self-assembly of a sulphur-terminated graphene nanoribbon within a single-walled carbon nanotube, Nature Mater., vol. 10, p. 687-692, 2011. 

Under electron irradiation (or by other mechanisms) it is possible to generate carbon vacancies leading to the formation of extended defect domains (with the presence of pentagonal and heptagonal, and even four-membered carbon rings) showing semiconductor character. This is the mechanism of formation of semiconductor properties in quantum-dot carbon nanoparticles or graphene nanoribbon. The mechanism... 

Yu, S.-S. Zheng, W.-T., Effect of N/B doping on the electronic and field emission properties for carbon nanotubes, carbon nanocones, and graphene nanoribbons. Nanoscale 2010,2 1069-1082. 

The Number of Conjugated Circuits in Nanotubes. Lukovits and Janezic182 calculated the number of conjugated circuits in armchair (1,1 ) carbon nanotubes and ( , )i nanoribbons and used them to obtain the resonance energies per electron (REPE) of these structures. For any (1,1) , nanotube, they derived the following formulae for 6- and 10-membered circuits in terms of the corresponding Kekule structures ... 

Kyotani, M. Yamaguchi, C. Goto, A. Sasaki, K. Matsui, H. Koga, Y. Nanoribbon graphite from carbyne like carbon. Synth. Metals 2001, 121, 1237-1238. 

Using the same method, Cotet and co-workers [54] prepared high-content Ee-, Co-, Ni-, Cu-, and Pd-doped carbon aerogels. The metal content of these samples was around 20 wt%, except in the case of the Pd-containing sample, where it was as high as 46 wt%. Mean crystallite size ranged from 12 to 40 nm and the surface areas from 370 to 450 m /g. The presence of some graphitic nanoribbons was detected in some of the prepared samples, as reported previously by other authors [42,51,55]. 

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