Graphene with line defect as a membrane for gas separation: Design via a first-principles modeling

A new line defect consisting of a sequence of octagons and all-hydrogen passivated pores in graphene was designed as a gas separation membrane using first-principles calculations. The all-hydrogen passivated pore produces a formidable barrier of 1.5 eV for CH4 but an easily surmountable barrier of 0.12 eV for H-2. Hence it exhibits extremely high separation capability in favor of H-2 among all studied species with the selectivity on the order of 10(22) for H-2/CH4. These results suggest that such a line-defect-containing graphene-based membrane could play a great role on numerous clean energy applications. (c) 2012 Elsevier B.V. All rights reserved.