Water-Induced Interactions between Boron-Doped Carbon Nanotubes

Abstract

Molecular dynamics (MD) simulations are used to investigate the hydration, the water-induced interactions, and the dispersion behavior of boron-doped single-walled carbon nanotubes (B-CNTs) within aqueous solutions. Models of B-CNTs with various diameters and B-doping patterns are developed, with partial charges calculated from first-principles density functional theory (DFT). Using MD simulations, the potential of mean force (PMF) of one, two, and three solvated B-CNTs are evaluated, and these results are compared to pristine CNTs. The hydration behavior of the B-CNTs is also quantified by evaluating the water density profiles and hydrogen bonds during the solvation. Our MD simulations indicate the presence of water-induced interactions with B-CNTs over prolonged distances, as compared to pristine CNTs. In particular, the B-CNTs are more resistant to reaggregation than pristine CNTs. These simulation results thoroughly characterize the effects of substitutional doping of CNTs on their dispersion behavior in aqueous solution, and our atomistic simulations of B-CNTs are used to parametrize coarse-grained models of the nanotube–nanotube interactions