Au nanoparticle-based multilayer ultrathin films with covalently linked nanostructures : Spraying layer-by-layer assembly and mechanical property characterization

We have studied electrostatic layer-by-layer spraying assembly of inorganic/organic nanocomposite multilayered films consisting of Au nanoparticle (Au NP) and photosensitive polycation nitrodiazoresin (NDR). A uniform growth of the Au NP-based assembly film is revealed by UV−vis spectroscopy and AFM-film thickness measurements. We demonstrate that cross-linked films can be produced by UV irradiation which induces the conversion of originally ionic bonds into covalent ones. The nanostructure of the film such as the thickness and the fraction of Au NP can be tailored by the adsorption conditions. Thus, we find that the mechanical properties, which were measured using a buckling test method, can be tailored to a certain degree.