Building 3D Layer-by-Layer Graphene−Gold Nanoparticle Hybrid Architecture with Tunable Interlayer Distance

The ability to construct self-assembled three-dimensional (3D) superstructures with desired functionality is not only of scientific curiosity but also crucial in the bottom-up nanofabrication of smart materials and devices. Here a facile solution-processable strategy for creating 3D layer-by-layer graphene−gold nanoparticle architectures was developed in which cysteine molecules with amino groups were chemically grafted onto the surface of graphene oxide and then the cysteine thiol groups were attached to the surface of gold nanorods (GNRs) through strong covalent Au−S linkages. In this self-assembled structure, as revealed by transmission electron microscopy (TEM) and scanning electron microscope (SEM), it was confirmed that the graphene layers aligned in parallel fashion rather than randomly to each other by the lying down patterns of the GNRs, which also formed layers in parallel. Furthermore, spherical gold nanoparticles with different sizes were used to control the interlayer distance of the 3D hybrid structure.