Two-dimensional nanopores and nanoporous membranes for ion and molecule transport

Two-dimensional (2D) materials from graphene to metal dichalcogenides and beyond, have interesting electrical, optical and mechanical properties. Recent advances in their growth, transfer and device physics have led to the shrinking of 2D material-based devices to the atomic scale and expanding their functionality. Single or multiple nanometer-scale holes, as small as single-atom vacancies, can be introduced in suspended atomically-thin 2D membranes, giving rise to nanopore and nanoporous devices, respectively. While engineering vacancies and holes is interesting for modulating optoelectronic properties, one equally fascinating research focus is ion and molecule transport through such pores in thin membranes. Here, we review the advancement of 2D nanopore science and technology for biomolecular detection and analysis, including DNA sequencing, and the largely parallel efforts towards development of 2D nanoporous membranes for ion selectivity and water desalination, both directions sharing similar fundamental principles.