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arXiv · 2009.13611

Water diffusion in carbon nanotubes: interplay between confinement, surface deformation and temperature

Bruno H. S. Mendonça·Patricia Ternes·Evy Salcedo·Alan B. de Oliveira·Marcia C. Barbosa
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Abstract

In this article we investigate through molecular dynamics simulations the diffusion behavior of the TIP4P/2005 water when confined in pristine and deformed carbon nanotubes (armchair and zigzag). To analyze different diffusive mechanisms, the water temperature was varied from $210\leq T\leq 380$~K. The results of our simulations reveal that water present 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 a mobility independent of the activation energy.

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Bruno H. S. Mendonça, Patricia Ternes, Evy Salcedo, Alan B. de Oliveira, Marcia C. Barbosa. 2020-09-28. Water diffusion in carbon nanotubes: interplay between confinement, surface deformation and temperature. https://doi.org/10.1063/5.0031084

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