Confined and mediated intercalation of nanoparticles in graphene oxide membrane to fine-tune desalination performance

Abstract

Multilayered graphene oxide (GO) membranes with interlayered sub-nanometer channels have attracted considerable interest for selective water and ion transport. However, the tortuous transport pathways and water-swelling characteristics of GO laminates hinder the desalination performance of such membranes. Modifying the interlayer through nanoparticle intercalation is one of the most prevalently employed methods of enlarging the nanochannels for rapid transport. However, this generally results in significantly reduced separation precision. In this study, we develop a confined interlayer with mediated nanoparticle intercalation to precisely modulate GO membranes. Enhanced water transport and high ion retardation were simultaneously achieved. We investigated the roles of confinement and mediation in the intercalation modification of GO laminates and highlighted their indispensability in realizing an efficient and effective desalination process. This strategy may also be applicable to the fine-structure control of other two-dimensional laminates.