Synthesis and applications of several curved polycyclic aromatic hydrocarbons

This thesis describes the synthesis and applications of two curved polycyclic aromatic hydrocarbons, hexabenzocoronene (HBC) and pentabenzocoronene (PBC). In Chapter 2, a monolayer of a carboxylic acid functionalized HBC is incorporated into an ultra small nanotube junction (∼ 2 to 6 nm). The junction is formed by cutting a single carbon nanotube using both electron beam lithography and oxygen plasma. These HBC-filled junctions are effective organic field effect transistor devices when the two ends of the nanotube are used as electrodes. As the molecules are exposed, they are sensitive to the environment and are capable of detecting electron deficient aromatic compounds such as TCNQ. In Chapter 3, the synthesis of PBC and several of its derivatives is described. The application of alkoxylated derivatives of PBC as discotic liquid crystals and as n-type organic field effect transistors is discussed. In Chapter 4, possible methods for incorporating HBC and PBC into the templated growth of carbon nanotubes are described. If successful, this would allow for the synthesis of carbon nanotubes samples with a single chiral index. For accurate spectroscopic characterization of single carbon nanotubes, unbundled carbon nanotubes are desired. Nanoparticle size has a strong correlation to carbon nanotube diameter. As such, for this project, well separated and uniformly sized nanoparticles are necessary. Arrays of catalyst nanoparticles have been synthesized using diblock copolymer templates, which allow the size and separation to be tuned. The stability and carbon nanotube growth activity of copper, ruthenium and cobalt nanoparticle arrays are presented.