Immobilization of Gold–Aryl Nanoparticles Over Graphene Oxide Platforms: Experimental and Molecular Dynamics Calculations Study

Graphene oxide (GO) was decorated with gold–aryl (Au–C) nanoparticles of AuNPs–COOH by sodium borohydride reduction of aryldiazonium tetrachloroaurate(III) salt at room temperature in aqueous solutions. Morphology of AuNPs–COOH/GO nanocomposite (NC) was probed using atomic force microscopy (AFM) and transmission electron microscopy (TEM), showing NC surface roughness and wrinkling. X-ray photoelectron spectroscopy (XPS) results suggest the clear reductive reaction of tetrachloroaurate anion into metallic gold in AuNPs–COOH/GO along with detailed interpretations of the nature of the functional groups. Brunauer–Emmett–Teller measurements supported GO anchoring by AuNPs modified with COOH; surface area dropped significantly. Molecular dynamics calculations endowed support of favorable wrinkling at the edges and carboxyl intercalation to GO surface of types π–π, hydrogen bonding, and hydrophobic interactions. Solvent accessible surface area calculations of GO showed a decrease in total surface area.