▎ 摘　　要

A wavy structure of the surface of graphene nanoparticles on a hydrocarbon substrate has been obtained. It has been shown that the wavy surface is the manifestation of the Kelvin-Helmholtz instability at the interface between liquid paraffin and graphene suspension with the inhomogeneity length lambda = 250 nm. The manifestation of such wavy structures is due primarily to van der Waals forces.