The advent of graphene and other two-dimensional materials in membrane science and technology

In this review, we discuss the potential of graphene and two dimensional materials 'beyond graphene' in membrane science, emphasizing peculiarities, application fields, open challenges and pitfalls. Two-dimensional materials are envisaged to work as ultrathin membranes with atomic thickness or, alternatively, as nanofillers for composite polymeric membranes. Formation and uniformity of nanopores into membranes based on two-dimensional materials represent key issues for successful separations. Currently, many efforts are dedicated to identify suitable techniques for massive production of porous graphene nanosheets at competitive costs. Despite a certain discrepancy between molecular modeling and experimental studies exists, the earliest implementations of graphene-based membranes for water desalination, liquid separation and gas purification show superb performances in terms of salt rejection, transmembrane flux and selectivity. Likewise, two-dimensional materials beyond graphene are regarded as promising candidates to work as ultrathin membranes.