Graphene kirigami membrane with superior theoretical permeability and adjustable selection capability

Membrane plays a central role in molecule separation and selection. However, most artificial membranes utilise a fixed passage size and only effective for limited molecule types. Here, via a large series of molecular and first-principles calculations, we reveal the potential of graphene kirigami (GK), a novel structure with nanoscale incisions on one-atom-thick graphene, which can transform into a threedimensional structure under deformation, as an ultra-membrane for highly adjustable molecule selection and the practical fabrication feasibility of GK-like membranes using a novel selective tearing process on initially defected graphene. Facilitated by the high stretchability of GK-based membranes, we demonstrate a wide range of gas selection capability on a single membrane. The interaction energy of adsorbed gas molecule also shows that the unique geometry of the pores on GK enables a new adsorption channelling mechanism that enhances molecular separation. Compared with nanoporous graphene, the dynamic gas penetration test shows that various GK membranes are capable of 30 times higher pore-size adjustability and up to 1.5-3.4 times higher gas separation rate. The GK ultramembrane opens new venues for numerous applications in CO2 capture and storage, water desalination, wastewater treatment, hazardous waste containment system, chemical processing, bionics, and pharmaceutical and medical devices. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Graphene kirigami (GK) shows potential for highly adjustable molecule selection with variable pore sizes, and can be fabricated using a novel selective tearing process on initially defected graphene. The GK ultramembrane demonstrates superior gas separation capabilities compared to nanoporous graphene.