Facile stabilization of gold-silver alloy nanoparticles on cellulose nanocrystal

Uniform Au-Ag alloy nanoparticles have been synthesized on cellulose nanocrystal (CNXL) by the co-reduction method of corresponding metal ions. CNXL that plays a dual role of a matrix and of a stabilizer has been used to obtain stable dispersions of alloy nanoparticles. The composition of alloy nanoparticles indicates a quantitative deposit of metal ions on CNXL surface followed by reduction. The sizes of alloy nanoparticles were controlled in the range of 3-7 nm by capping agent, sodium citrate, and their average diameter was increased with an increase of Ag content. Aqueous suspensions of Au-Ag alloy nanoparticles and their dried films are characterized by UV-vis spectroscopy, field emission-scanning electron microscope (FE-SEM), transmission electron microscope (TEM), and X-ray diffraction (XRD).