NSF-EC Activity: Experimental and Theoretical Studies of Intercalated and Intracalated Carbon Nanotubes

University Of Pennsylvania, Philadelphia PA

Investigators

Abstract

The intrinsic structure and chemistry of nanotubes provide a framework upon which important functional nanoscale systems can be built. At the University of Pennsylvania, we are discovered and produced hybrid materials in which molecules are introduced into the lumen of nanotubes to impart new and improved functionality. The first of these was one-dimensional chains of C(60) molecules encapsulated in single-wall carbon nanotubes. The molecules were shown to be highly mobile within the tubes and therefore provide an ideal basis for the experimental and theoretical study of one-dimensional systems. We have recently shown that our synthesis methods are general and we have incorporated the alkali metals K and CS, and the endohedral molecule La(2)@C(60), inside of nanotubes. This can lead to important results. For example, calculations predict that the tensile modulus of nanotubes is greatly increased when they contain chains of C(60). Also, there are possible applications of these systems to hydrogen storage and Li-based batteries. An exciting prospect is the use of nanotubes as nanoscale reaction chambers to produce metastable molecules. %%% Our theory program first developed the intermolecular potentials among graphitic and fullerene structures and then applied one-dimensional statistical mechanics to analyze the clustering and one-dimensional equation of state of fullerene chains within nanotubes.