Synthesis of gelatin-stabilized concentrated hydrosols of copper nanoparticles

Abstract

The effect of the copper sulfate, hydrazine, and gelatin concentrations, as well as of the Bloom strength of gelatin, pH, and synthesis temperature on the formation of copper nanoparticles via copper(II) sulfate reduction with a hydrazine solution has been evaluated. Conditions for the formation of oxidation- and aggregation-resistant concentrated (up to 0.4 M) copper metal hydrosols have been found. According to the transmission electron microscopic data, the resulting hydrosols contain metallic copper nanoparticles shaped as polyhedra with six poorly defined facets, having an average size of 30–60 nm, stabilized by a gelatin layer (2–3 nm).