Fullerene Coalescence into Metallic Heterostructures in Boron Nitride Nanotubes:A Molecular Dynamics Study

摘要

We report the full molecular dynamics simulations for fusing the encapsulated fullerene linear chain into a single-walled carbon nanotube when the boron nitride nanopeapods undergo thermal annealing at high temperature.Such supramolecular coalescence inside a one-dimensional confining environment,involving fullerene polymerization and surface reconstruction,is driven by surface and strain energy minimization.The evolution of vacancies and isomerization of carbon rings play the dominant role in the structural transformation.The internal pressure and temperature are crucial for the merging of fullerene molecules and the formation of corrugated carbon nanotube cores.Within the ab initio framework,we investigate the electronic,transport,and magnetic properties of heterostructures after phase transformation.The results indicate that the new phase is metallic due to a core of corrugated carbon nanotube,which provides an electron transport channel.Further analyses of energy bands and spin densities reveal the possibility of flat-band ferromagnetism in the heterostructures.