In this work, we present a systematic and thorough comparison between gas adsorption and energy storage properties in idealized or realistic models of organic-pillared reduced-graphene-oxide sheets. First, atomistic simulations based on density functional theory are used to generate the structures of these novel systems. Second, Grand Canonical Monte Carlo is used to predict the adsorption properties of the proposed frameworks in the case of two different gases, notably hydrogen and carbon dioxide. While one can safely conclude that gas adsorption is strongly affected by the density of the pillars and the chemical composition of the compounds, a comparison between realistic idealized structures shows that even the corrugation of graphene sheets has a deep impact on such properties. Finally, we produce evidence of the potentiality of these pillared structures to be used as gas separation devices by investigating the sieving of an equimolar CO2/H2 mixture at room temperature.
Date of publication:
J. Phys. Chem. C, 2015, 119 (4), pp 1980–1987