(Photo)chlorination-induced physicochemical transformation of aqueous fullerene nC60.

This study confirmed the physicochemical transformation of aqueous fullerene aggregates (nC(60)) produced via solvent exchange from toluene by chlorine in the dark and under fluorescent light (representing visible light) by comparing the changes in light absorbance at 700 nm and size distribution of nC(60) and characterizing the photochlorination products of nC(60) by XPS, FTIR and TOF-SIMS techniques. The (photo)chlorination of nC(60) was enhanced by increasing the chlorine dosage and the salinity concentration, and the presence of fluorescent light. During (photo)chlorination, nC(60) underwent surface chlorination, hydroxylation and oxidation, and was transformed into products containing carbon-chlorine, epoxy and hydroxyl functional groups. Extensive (photo)chlorination produced products that might not possess the isolated benzenoid ring structure on their cages, although they retained the 60-carbon cage structure. These findings imply the necessity of assessing the fate and toxicity of nC(60) after (photo)chlorination in both engineered and natural environments and demonstrate a simple way to produce new nC(60) derivatives that contain chlorine and oxygen.