Abstract: Electrostatic self-assembly technique was used to prepare Au-nanoparticle/polyelectrolyte multilayers. The microstructures of the films were characterized by X-ray reflectivity and the atomic force microscopy. It is found that when the polyelectrolyte layers under the Au nanoparticles were thin, there were no clear interfaces in the films; when the polyelectrolyte layers got thick, the interfaces become clear. Therefore, it needs to increase properly the thickness of the polyelectrolyte layers in order to get the metal nanoparticle/polyelectrolyte multilayers with clear interfaces.

Key words: Electrostatic self-assembly, Polyelectrolyte, Multilayer films, Interfaces, X-ray reflectivity