Interactions Between Polycyclic Aromatic Molecules And Single-Walled Carbon Nanotubes

This work aimed at understanding the interactions between polycyclic aromatic molecules and single walled carbon nanotubes (SWNTs). Effects of polycyclic aromatic molecules' structure on the molecule/SWNT interaction were investigated and the mechnism that underlying were discussed. Additionally, attempts were made to separate the enatiomers of SWCNTs using chiral polycyclic aromatic molecules. The main findings of the work are:1. The non-covalent functionalization of SWNTs using a series of polycyclic aromatic molecules containing hetero atoms were studied. The adsorption ratio data revealed that N atom, either in the form of hetero atom or amino group, improved the adsorption affinity between the molecules and the SWNTs. In contrast, the existences of O or S hetero atom in the framework were found to decrease the adsorption affinity. This finding provides useful information for the future selection of aromatic molecules for SWNT modification.2. Fluorescence titration and time-resolved fluorescence measurements were performed to investigated the mechanism of SWNT induced fluorescence quenching of the aromatic molecules. Fluorescence lifetime decays exhibit no obvious change upon addition of different amount of SWNTs, which reveals that the static quenching mechanism is dominate in such molecule/SWNT systems. The understanding of the fluorescence quenching mechanism may help to design novel photoelectronic based on SWNT/molecule complex.3. Attempt have been made to solve the challenge of separating SWNT enatiomers using chiral polycyclic aromatic molecules.. Our preliminary results showed chiral BINOL exhibited low efficient in separating SWNT enatiomers, which is attributed to the low conjugation of naphthalene rings and their easy rotation in solution. These factors should be considered in the future optimization of the separating molecules.