Two-dimensional fullerene-graphene heterochannel membranes with ultrahigh ambient-temperature solvent vapor flux

Two-dimensional (2D) nanomaterial membranes hold great promise for energy-efficient organic solvent separation, yet achieving both high permeability and selectivity remains challenging due to membrane swelling and poorly understood transport mechanisms. Here, we report (C₆₀)_∞-graphene heterochannel membranes fabricated via thermal reduction of alternately stacked hydroxylated (C₆₀–OH)_∞ and graphene oxide nanosheets. Removal of functional groups reduces transport resistance and improves the rejection. The resulting membranes exhibit exceptional ambient-temperature vapor flux from nonpolar (1286.8 and 831.7 kg m⁻² h⁻¹ for acetone and hexane, respectively) to polar (304.3 and 146.15 kg m⁻² h⁻¹ for methanol and water, respectively) organic solvents with complete dye rejection due to the confinement, which is superior to those of the state-of-the-art materials. Experimental and computational studies reveal that sub-nanometer topological features from periodic C₆₀ clusters and flat graphene create spatially heterogeneous transport pathways where fluid densities are largely reduced and thus induce fast slip flow. We develop a subcontinuum framework that accurately captures solvent permeation across diverse 2D channel architectures, bridging molecular-scale features under subnanometer confinement to membrane-level performance and enabling topology-guided membrane design.