Cyclopentadienyl, cobaltocene systems

Nikolaev, P. Bronikowski, M. J. Bradley, R. K. Rohmund, E. Colbert, D. T. Smith, K. A. Smalley, R. E. Chem. Phys. Lett. 1999, 313, 91. It should be noted that Ee(CO)5 is not the only system in which the precursor acts as the metal catalyst and carbon source. A number of metallocenes (e.g., ferrocene, cobaltocene, and nickelocene) have also been used however, they typically result in MWNT growth rather than SWNTs. This is most likely due to the larger number of carbon atoms from cyclopentadienyl groups that must self-assemble, relative to smaller carbon precursors (e.g., CH4, C2H2, etc.) used for SWNT growth. 

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