Linear Assemblies of Monodisperse Silver Nanoparticles on Micro/Nanofibrillar Cellulose

Abstract

Uniform silver nanoparticles with diameters smaller than 10 nm have been synthesized by the hydrothermal method on micro/nanofibrils of cellulose, which is used as a substrate, in a solution consisting of a water/ethylene glycol (reductant) mixture, a silver salt, poly(vinylpyrrolidone), and silver chloride used as a seed. Cellulose plays the role of an additional mild reductant, which prevents the formed nanoparticles from coalescence and provides the formation of their linear assemblies, in which the density of the nanoparticles and the gaps between them are regulated by varying silver salt concentration in the reaction mixture. Experiments performed with rhodamine 6G dye have shown that the synthesized assemblies of silver nanoparticles exhibit surface-enhanced Raman scattering. The proposed synthesis method may be used for the production of inexpensive sensor elements for surface-enhanced Raman scattering spectroscopy analysis.