Water diffusion in carbon nanotubes : Interplay between confinement, surface deformation, and temperature
Mendonça, Bruno Henrique da Silva e, Ternes, Patrícia, Torres, Evy Augusto Salcedo, Oliveira, Alan Barros de, Barbosa, Marcia Cristina Bernardes
Abstract
In this article, we investigate, through molecular dynamics simulations, the diffusion behavior of the TIP4P/2005 water confined in pristine and deformed carbon nanotubes (armchair and zigzag). To analyze different diffusive mechanisms, the water temperature was varied as 210 ≤ T ≤ 380 K. The results of our simulations reveal that water presents a non-Arrhenius to Arrhenius diffusion crossover. The confinement shifts the diffusion transition to higher temperatures when compared with the bulk system. In addition, for narrower nanotubes, water diffuses in a single line, which leads to its mobility independent of the activation energy.