High-conductivity graphene nanocomposite via facile, covalent linkage of gold nanoparticles to graphene oxide

Graphene and its derivative, graphene oxide (GO) have been substantively used as the main framework for dispersing or building nanoarchitectures because of their excellent properties in electronics and catalysis. The requirement to obtain superior graphene-metal hybrid nanomaterials has led us to explore a facile way to design 4-aminobenzenethiol/1-hexanethiolate-protected gold nanoparticles (aAuNPs)-functionalized graphene oxide composite (aAuNPs-GO) in solution. We demonstrate that when aAuNPs with amino groups are exposed to GO, well-dispersed coverage of Au nanoparticles are mainly observed on the edge of GO sheet. In contrast, when 1-hexanethiolate-protected gold nanoparticles (hAuNPs) without amino groups are exposed to GO, hAuNPs simply aggregate on the surface of GO. This indicates that amino groups located on the surface of Au nanoparticles are an essential prerequisite for attachment of nearly monodispersed aAuNPs. The strategy described here for the fabrication of aAuNPs-GO provides a straightforward approach to develop graphene-based nanocomposites with undamaged sheets structure and good solubility and also improve the conductivity of GO sheets evidently.