A Morphology‐Selective Copper Organosol

Abstract
Hexagonal colloidal copper particles with a narrow size distribution are formed in the reduction of an acetonitrile solution of Cu(OAc)2·H2O with hydrazine hydrate in the presence of poly(vinyl‐2‐pyrrolidone). The deep‐red sols, which were characterized by electron microscopy, are extremely stable in an inert gas atmosphere. They can be redispersed even after complete drying. An insoluble red film is however formed when the dried sol is heated for 30 minutes; this process probably involves polymer cross‐linking.