Polyelectrolyte assisted silver nanoparticles synthesis and thin film formation

Silver nanoparticles were prepared by the reduction of silver salts with sodium borohydride and capped with a copolymer of styrene sulfonate and maleic monomers. The synthesized nanoparticles were then deposited on a glass substrate using the layer-by-layer deposition technique in alternance with polycationic poly(diallyl-dimethylammonium chloride) PDADMAC. The synthesis of the silver nanoparticles as well as the layer-by-layer deposition with PDADMAC was easily monitored by UV–Vis spectroscopy due to the strong plasmon absorbance at 400 nm of the silver nanoparticles. Our study shows that increasing the concentration ration between the co-polyelectrolyte and silver nitrate has a negative effect on the size distribution of the resulting silver nanoparticles. For the layer-by-layer assembly, the PSS-co-Maleic was found to be a good capping agent since it allows later the formation of uniform thin films when deposited with PDADMAC. A linear increase in absorbance as a function of the number of deposited layers was observed.