Controlled deposition of silver nanoparticles in mesoporous thin films: towards new metallic-oxide nanocomposites

Metal-oxide nano composites made up of Ag nanoparticle (NP) assemblies embedded within meso porous oxide thin films were produced by mild reduction of Ag adsorbed onto the pore surface. The nano composites were characterized by small angle x-ray scattering (2D SAXS, DO3A SAXS2) and X-ray reflectometry (XRR, D10A XRD2). A quantitative method based in XRR was developed in order to assess pore filling. Inclusion of Ag NP assemblies in meso porous SiO2 or TiO2 requires different processing conditions. The difference of reactivity of both oxide matrices towards Ag reduction is exploited to selectively synthesize NPs in a a pre-determined layer of a multilayered meso porous stack. This leads to highly controlled 1D ordered multilayers with precise spatial location of nano metric objects. (author)