Non-Covalent Functionalization of Graphene Using Self-Assembly of Alkane-Amines

A simple, versatile method for non-covalent functionalization of graphene based on solution-phase assembly of alkane-amine layers is presented. Second-order MollerPlesset (MP2) perturbation theory on a cluster model (methylamine on pyrene) yields a binding energy of 220 meV for the aminegraphene interaction, which is strong enough to enable formation of a stable aminodecane layer at room temperature. Atomistic molecular dynamics simulations on an assembly of 1-aminodecane molecules indicate that a self-assembled monolayer can form, with the alkane chains oriented perpendicular to the graphene basal plane. The calculated monolayer height (1.7 nm) is in good agreement with atomic force microscopy data acquired for graphene functionalized with 1-aminodecane, which yield a continuous layer with mean thickness 1.7 nm, albeit with some island defects. Raman data also confirm that self-assembly of alkane-amines is a non-covalent process, i.e., it does not perturb the sp2 hybridization of the graphene. Passivation and adsorbate n-doping of graphene field-effect devices using 1-aminodecane, as well as high-density binding of plasmonic metal nanoparticles and seeded atomic layer deposition of inorganic dielectrics using 1,10-diaminodecane are also reported.