A Generic Synthetic Approach to Large-Scale Pristine-Graphene/Metal-Nanoparticies Hybrids

摘要

The homogeneous attachment of metal-nanoparticles (metal-NPs) on pristine-graphene surface to construct pristine-graphene/metal-NPs hybrids is highly expected for application in many fields such as transparent electrodes and conductive composites. However, it remains a great challenge since the pristine-graphene is highly hydrophobic. Here, an environmentally friendly generic synthetic approach to large-scale pristine-graphene/ metal-NPs hybrids is presented, by a combinatorial process of exfoliating expanded graphite in N-methyl pyrrolidone via sonication and centrifugation to achieve the pristine-graphene, and attaching pre-synthesized metai-NPs on the pristine-graphene in ethanol via van der Waals interactions between the metal-NPs and the pristine-graphene. Nanoparticles of different metals (such as Ag, Au, and Pd) with various morphologies (such as sphere, cube, plate, multi-angle, and spherical-particle assembling) can be homogeneously attached on the defect-free pristine-graphene with controlled packing densities. Both the pristine-graphene and the metal-NPs preserve their original intrinsic structures. The as-synthesized pristine-graphene/Ag-NPs hybrids show very high surface-enhanced Raman scattering activity due to the combined effects of large surface area of the pristine-graphene to adsorb more target molecules and the electromagnetic enhancement of the Ag-NPs. This large-scale synthesis of the pristine-graphene/metal-NPs hybrids with tunable shape and packing density of metal-NPs opens up opportunities for fundamental research and potential applications ranging from devices to transparent electrodes and conductive composites.