Strain-Guided Oxidative Nanoperforation on Graphene.

Abstract

Increased applications of nanoporous graphene in nanoelectronics and membrane separations require ordered and precise perforation of graphene, whose scalablility and time/cost effectiveness represent a significant challenge in existing nanoperforation methods, such as catalytical etching and lithography. A strain-guided perforation of graphene through oxidative etching is reported, where nanopores nucleate selectively at the bulges induced by the prepatterned nanoprotrusions underneath. Using reactive molecular dynamics and theoretical models, the perforation mechanisms are uncovered through the relationship between bulge-induced strain and enhanced etching reactivity. Parallel experiments of chemical vapor deposition (CVD) of graphene on SiO2 NPs/SiO2 substrates verify the feasibility of such strain-guided perforation and evolution of pore size by exposure of varied durations to oxygen plasma. This scalable method can be feasibly applied to a broad variety of 2D materials (e.g., graphene and h-boron nitride) and nanoprotrusions (e.g., SiO2 and C60 nanoparticles), allowing rational fabrication of 2D material-based devices.