A novel method for the layer-by-layer assembly of metal nanoparticles transported by polymer microspheres

A novel method for the assembly of metal nanoparticles is reported, in which polymer microspheres have been employed as both stabilizers and transport vehicles. We prepared sulfonated polystyrene microspheres and then introduced silver ions into the microspheres by ion exchange. Dispersal of the polymer microspheres in DMF led to the silver ions in them being reduced by the solvent; the resulting Ag nanoparticles were stabilized by the polymer network. In aqueous solution, the polymer microspheres are negatively charged and, by using layer-by-layer method, the prepared Ag nanoparticles can be self-assembled into films using the microspheres as transport vehicles.