Graphene kirigami as an ultra-permeable water desalination membrane

Abstract

In the present study, we reveal the potential of graphene kirigami (GK) as an ultra-permeable membrane for water desalination using molecular dynamics simulation. The results demonstrate that the GK membrane has superior performance in water permeance, obtaining over 103 L/m2/h/bar with 100% salt rejection. The theoretical efficiency of water permeance using GK membrane is 2.4–5.8 times higher than that of the nanoporous graphene membrane and 2–4 orders of magnitude higher than reported conventional reverse osmosis membranes. Due to the unique geometry of the kirigami structure, the GK membrane would form the adsorption channels to reduce the energy barrier during the desalination processes and guide water molecules to be filtered more effectively. Moreover, compared with the nanoporous graphene, the GK membranes do not have rigorous pore geometry restrictions for desalination and can be generated via mechanical deformation, which provides significant convenience for future applications in practical projects.