Structuring of Graphene Oxide Interacting with Nanodiamonds in Aqueous Dispersions

Small-angle neutron scattering has been used to study the mechanisms of graphene oxide self-organization in aqueous dispersions during its interaction with detonation nanodiamonds having different surface potential signs. Being mixed with a hydrosol of positively charged diamonds, negatively charged graphene oxide yields a stable colloid due to the formation of planar heterostructures in the form of paired sheets tightly connected through diamonds (25 wt %) when the sheets are joined. Under similar conditions, diamonds with a negative potential are localized between graphene sheets to form, at an increased fraction (44 wt %), less dense assemblies with a gap between the sheets on the order of the diamond particle radius. The binding of graphene oxide to diamonds has been confirmed by transmission electron microscopy data.