Conversion of uniform colloidal Cu_2O spheres to copper in polyols

摘要

Colloidal copper particles with a high degree of crystallinity were obtained by heating solutions of copper(Ⅱ) acetate in ethylene glycol (EG) and tetraethylene glycol (TEG). The formation mechanism of copper particles involved first the formation of sparingly soluble nano-sized copper(Ⅰ) oxide, which aggregated into uniform spheres. On prolonged heating the Cu_2O particles were reduced to nano-sized copper crystallites followed by their sintering to colloidal metal. The conversion of the copper(Ⅰ) oxide to metallic copper proceeds uniformly within the body of each particle.