Preparation and characterization of copper and silver nanostructures

Abstract

In this study, we have prepared nanometer-sized copper and silver nanostructures using arrested precipitation and reverse micelle method. On preparing copper samples with alkanethiol, nanoparticles with 3-5 nm have been observed and properties relating to the copper cores were not detected. Instead, interdigitation of the alkanethiol chains between neighbouring clusters was suggested and such interdigitation could gradually be disrupted upon heating. While copper particle size decreased with increase in alkanethiol chain length, our prepared copper samples were similar in properties with copper bilayer compounds. Interestingly, dodecanethiol-protected copper/silver bimetallic nanoparticles were also found to have their surface enriched with copper atoms as a result of galvanic exchange reaction. On the other hand, we have noted that while the growth of silver nanoparticles in reverse micelles depends on the degree of nucleation and intermicellar collision, SiO2 is able to encapsulate copper nanoparticles more effectively in the reverse micelles without the use of thioglycerol.