Scalable Synthesis of Carbon Nanomembranes from Amorphous Molecular Layers

Nanoporous carbon nanomembranes (CNMs) created by self-assembledmonolayers ideally combine a high water flux and precise ion selectivityfor molecular separation and water desalination. However, their practicalimplementation is often challenged by the availability of large epitaxialsubstrates, limiting the membrane up-scaling. Here, we report a scalablesynthesis of CNMs from poly(4-vinylbiphenyl) (PVBP) spin-coated onSiO(2)/Si wafers. Electron irradiation of the amorphous PVBPmolecular layers induces the formation of a continuous membrane witha thickness of 15 nm and a high density of subnanometer pores, providinga water permeance as high as 530 L m(-2) h(-1) bar(-1), while repelling ions and molecules largerthan 1 nm in size. A further introduction of a reinforced porous blockcopolymer layer enables the fabrication of centimeter-scale CNM compositesthat efficiently separate organic dyes from water. These results suggesta feasible route for large-scale nanomembrane fabrication.