On an improved pyrolytic synthesis of [60]- and [70]-fullerene Original Research Article

The nickel-catalyzed pyrolysis of two fullerene precursors — (1) naphthalene and (2) 1-bromonaphthalene — at 1200°C in an argon atmosphere has been investigated. Fullerenes, polycyclic aromatic hydrocarbons (PAHs), and polycyclic aromatic brominated species (the latter obtained in pyrolysis of 1-bromonaphthalene only) were extracted from the pyrolysates by reflux in toluene. The toluene extracts were subjected to mass spectrometric analysis using the chemical ionization technique in the negative mode. Mass spectra are included with discussions on fullerene yields and on the mechanism by which fullerenes are formed in pyrolysis. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the toluene-insoluble material.