title: Catalyst design for carbon nanotube growth using atomistic modeling.
abstract: The formation and stability of bimetallic catalyst particles, in the framework of carbon nanotube growth, is studied using the Bozzolo-Ferrante-Smith (BFS) method for alloys. Monte Carlo-Metropolis simulations with the BFS method are utilized in order to predict and study equilibrium configurations for nanoscale catalyst particles which are directly relevant to the catalyst state prior to growth of carbon nanotubes. At the forefront of possible catalyst combinations is the popular Fe-Mo bimetallic catalyst, which we have recently studied experimentally. We explain our experimental results, which indicate that the growth observed is dependent on the order of co-catalyst deposition, in the straightforward interpretation of BFS strain and chemical energy contributions toward the formation of Fe-Mo catalyst prior to growth. We find that the competition between the formation of metastable inner Mo cores and clusters of surface-segregated Mo atoms in Fe-Mo catalyst particles influences catalyst formation, and we investigate the role of Mo concentration and catalyst particle size in this process. Finally, we apply the same modeling approach to other prominent bimetallic catalysts and suggest that this technique can be a powerful tool to understand and manipulate catalyst design for highly efficient carbon nanotube growth.
authors.affiliation: Department of Physics and Astronomy, Rice University, Houston, TX 77005, USA. Richard E Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, TX 77005, USA.
authors.forename: Cary L
authors.initials: CL
authors.lastname: Pint
authors.forename: Guillermo
authors.initials: G
authors.lastname: Bozzolo
authors.forename: Robert
authors.initials: R
authors.lastname: Hauge