Interaction of Substituted Aromatic Compounds with Graphene

Abstract

We have modeled the adsorption of various substituted derivatives of benzene on a graphene sheet, using a first-principles density functional theory−local density approximation method. The presence of functional groups can significantly alter the overall magnitude of π−π interactions between the adsorbed molecules and graphene by giving rise to strong medium-range interactions involving π-orbitals of the substituents. When the substituents can simultaneously permit the formation of hydrogen bonds between adsorbed molecules, it is possible to evaluate the relative contributions of hydrogen bonding and π-based interactions to the overall adsorption. Adsorption of individual molecules and hydrogen-bonded aggregates reflects a hierarchical balance of the different interactions that determine the overall energy of adsorption.