Researchers at Manchester University’s National Graphene Institute (NGI) have assembled 2D materials with sub-nanometre slits that hold potential for water desalination. The materials are made from graphene, hexagonal boron nitride (hBN) and molybdenum disulphide (MoS₂). According to the researchers, they were able to manufacture slits in these materials just several angstroms (0.1nm) in diameter. At this scale, it was possible to study how individual ions behaved while passing through the slits. The work, which is published in the journal Science, also sheds light on how similar scale biological filters function in nature.