Fluorescence spectroscopy of single-walled carbon nanotubes synthesized from alcohol

Near-infrared fluorescence measurements were performed on single-walled carbon nanotubes (SWNTs) catalytically synthesized from alcohol under various experimental conditions (alcohol catalytic CVD method, ACCVD). The chirality distribution was determined by measuring the fluorescence emitted from separated SWNTs as a function of excitation wavelength. Compared with HiPco SWNTs, chiralities of the ACCVD sample were distributed predominantly in the higher chiral angle region, close to the so-called armchair structure. This tendency toward higher chiral angles was more pronounced for smaller diameter nanotubes. The reason for the armchair-rich chirality distribution is discussed based on the initial cap structure satisfying the ‘isolated pentagon rule’.