Creating New Types of Carbon-Based Membranes

Graphene oxide membranes can show unusually high water permeability, and diamond-like carbon membranes exhibited ultrafast permeation of organic solvents. Carbon-based membranes (1) for gas separations, which can be produced by pyrolysis of various precursor polymers, have had limited commercial use to date, in part because of their high cost and fragile mechanical nature. In this issue, unusual permeation behavior is reported for membranes made from two quite different forms of carbon that make them attractive for molecular separations or perhaps other uses. On page 442, Nair et al. (2) describe extremely rapid permeation of water through graphene oxide (GO) membranes that are essentially impermeable to other liquids and to helium, while on page 444, Karan et al. (3) report ultrafast permeation of organic solvents through diamond-like carbon nanosheets that reject larger dissolved molecules.