State-of-the-Art and Future Prospects for Atomically Thin Membranes from 2D Materials.

Atomically thin 2D materials, such as graphene, hexagonal boron-nitride, and others, offer new possibilities for ultrathin barrier and membrane applications. While the impermeability of pristine 2D materials to gas molecules, such as He, allows the realization of the thinnest physical barrier, nanoscale vacancy defects in the 2D material lattice manifest as nanopores in an atomically thin membrane. Such nanoporous atomically thin membranes (NATMs) present potential for enabling ultrahigh permeance and selectivity in a wide range of novel separation processes. Herein, the transport properties observed in NATMs are described and recent experimental progress achieved in their fabrication is summarized. Some of the challenges in NATM scale-up for practical applications are highlighted and several opportunities are identified, including the possibility of blending traditional membrane-processing approaches. Finally, a technological roadmap is presented with a contextual discussion for NATMs to progress from research to applications.