Ultrafast water diffusion along the interface between oxidized and pristine regions in graphene oxide: Reactive molecular dynamics study

Abstract

Graphene oxide (GO) is a promising membrane material due to its high water permeability. However, the exact physical mechanisms governing this process at the molecular level remain poorly understood, despite more than a decade of practical applications. In this article, we use classical molecular dynamics with the reactive potential ReaxFF to study the mobility of water molecules intercalated in GO and analyze the influence of its structure on diffusion processes. We highlight the previously unmentioned role of the interfacial area between oxidized and pristine graphene regions, which, according to our calculations, may be responsible for the ultrafast water transport observed in GO. This diffusion exhibits characteristics of a ballistic regime, suggesting another possible mechanism underlying GO’s high water permeability.