Graphene Membraned Blocks Helium and Other Gasses, Allows Water Through

To explain how this was possible, the authors hypothesized that the size between the layers of graphene were just right. They suggest that, at a free channel spacing of just about five angstroms, a monolayer of water forms that is capable of undergoing a low-friction flow in the two-dimension channels that exist between the layers (take that, no slip hypothesis!). To move between layers—and hence traverse the membrane—the authors posit that a percolating network of graphene nanocapillaries exists that allows the water to flow throughout and across the membrane.