(590f) From Feedstock to Final Product: Toward Molecular Dynamics Simulations Encompassing All Stages of Single-Walled Carbon Nanotube Synthesis

Carbon nanostructures are increasingly finding applications in a wide range of technologies. Because many of these applications are sensitive to the atomic structure of the nanotubes, their full realization is contingent on our ability to selectively produce or synthesize particulars target structures. Within this context the synthesis of single-walled carbon nanotubes (SWNT) with predefined diameters or other structural properties is highly desirable. While progress has already been made toward this end, further headway would be greatly advanced by a detailed understanding of the mechanisms involved in the synthesis process. Atomistic modeling is making unique contributions to efforts to understand the details of SWNT nucleation and growth. These insights have typically been gleaned by modeling a particular stage in isolation from the rest of the overall process. We have used the ReaxFF reactive force field to model SWNT growth on realistically-sized nickel nanocatalysts within a single molecular dynamics simulation starting with gas phase acetylene feedstock and ending with a SWNT nucleus containing hundreds of carbon atoms. This enables us to follow the individual atomistic processes involved and map out how these mechanistic details work together within the overall synthesis. Furthermore our simulations demonstrate the feasibility of realistically modeling all phases of SWNT synthesis within a single molecular dynamics simulation.