Functionalized Carbon Honeycomb Membranes for Reverse Osmosis Water Desalination

Reverse osmosis desalination is a common technique to obtain fresh water from saltwater. Conventional membranes suffer from a trade-off between salt rejection and water permeability, raising a need for developing new classes of membranes. C-based membranes with porous graphene and carbon nanotubes offer high salt rejection, water permeability, and fouling resistance. However, controlling the pore size of these membranes is challenging. Therefore, a carbon honeycomb membrane is studied using classical molecular dynamics simulations. It is reported that functionalization with −COO^– groups provides 100% salt rejection with around 1000 times higher water permeability than conventional polyamide membranes. Atomic-level understanding of the effect of the functional groups' location on salt rejection and water permeability is developed.