Unravelling the mechanisms behind mixed catalysts for the high yield production of single-walled carbon nanotubes
S. Tetali, M. Zaka, R. Schönfelder, A. Bachmatiuk, F. Börrnert, I. Ibrahim, J. H. Lin, G. Cuniberti, J. H. Warner, B. Büchner, and M. Rümmeli
ACS Nano 3, 3839 (2009)
The use of mixed catalysts for the high-yield production of single-walled carbon nanotubes is well-known. The mechanisms behind the improved yield are poorly understood. In this study, we systematically explore different catalyst combinations from Ni, Co, and Mo for the synthesis of carbon nanotubes via laser evaporation. Our findings reveal that the mixing of catalysts alters the catalyst cluster size distribution, maximizing the clusters' potential to form a hemispherical cap at nucleation and, hence, form a single-walled carbon nanotube. This process significantly improves the single-walled carbon nanotube yields.