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The vital effect of the polyaromatic hydrocarbon for the formation of fullerenes.

Tremendous advances in nanoscience have been made since the discovery of fullerenes. However, the short timescale of the growth process and high-energy conditions of synthesis result in severe constraints to the investigations of fullerene formation mechanism. This work attempted to reveal the formation process via analyzing the variation of the yield of fullerenes. Experiments and theoretical analysis show that the formation of fullerenes could be affected by the addition of polycyclic aromatics. It is proposed that the formation of C 60 during arc discharge synthesizing is fragment assembling, while the yield of C 2m (m=35, 38, 39) is strongly enhanced by building block splicing. In addition, several features of the building blocks are put forward to predict the extent of their influence to the formation of larger fullerenes C 2n (n≥42). This work not only provides essential insight into the formation process of fullerenes, but more importantly also to improve the yield of larger fullerenes selectively.