Nano “onions”, fullerene

The discovery of fullerenes in 1985 led to the era of nanomaterials.1 The three-dimensional geometry of these molecules as well as their unique properties distinguishes them from conventional molecules encountered in organic chemistry. Due to recent discoveries in this field, the horizons of this area have broadened to encompass various new molecules such as endohedral fullerenes, nanotubes, carbon nanohorns, and carbon nano-onions. This chapter discusses the electrochemical behavior of some of these carbon nanoparticles with special emphasis on endohedral fullerenes. Since a large number of fullerene derivatives have been prepared and their various electrochemical studies in different solvents and electrolytes have been reported, the electrochemistry of these derivatives is beyond the scope of this text.2 3 Among the other carbon nanoparticles, the electrochemistry of derivatives of carbon nanotubes has been reported. These studies have been highlighted in the final part of the chapter. 

Carbon soot, as might be seen in Figure 1.10, already possesses a structure very much alike that of nano-onions. Only the roof tile arrangement of the graphene platelets in soot differs from the concentric pattern of intercalated fullerenes in the onions. Hence, it is self-suggesting to try preparing carbon onions from diverse soot materials. 

Recently, a functionalization of carbon nano-onions (CNO, multilayer fullerenes) was carried out by [2+1] cycloaddition of nitrenes. The grafted products were prepared by the grafting-from method combining in situ ring-opening polymerization (ROP) and ATRP [127]. 

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