  Angstrom confined solvents in two-dimensional laminates travel through
interlayer spacings, gaps between adjacent sheets, and via in plane pores.
Among these, experimental access to investigate the mass transport through in
plane pores is lacking. Here, we create these nanopores in graphene oxide
membranes via ion irradiation with precise control over functional groups, pore
size and pore density. Low ion induced pore densities result in mild reduction
and increased water permeation for the membranes. Higher pore densities lead to
pronounced reduction and complete blockage of pure water however allows
permeation of ethanol water mixture due to weakening of hydrogen network. We
confirm with simulations, that the attraction of the solvents towards the pores
with functional groups and disruption of the angstrom confined hydrogen network
is crucial to allow in plane pore transport.
