Synthesis and Electrophoretic Concentration of Ag–Cu Nanoparticles of the Core–Shell Type in an AOT Microemulsion in n-Decane

Stable organosols of silver and copper bimetallic nanoparticles were obtained in sodium bis(2-ethylhexyl) sulfosuccinate (AOT) reverse micelles in the emulsion and microemulsion variants and characterized by physicochemical methods. The adsorption layer of nanoparticles in AOT solutions in n-decane was found to have a complex multilayer structure; an increase in the mole fraction of copper led to an increase in the hydrodynamic diameter of nanoparticles from 14 to 23 nm and a decrease in the electrokinetic potential from 18 to 7 mV. The surface charge of nanoparticles can be increased by diluting the sols with chloroform, and electrophoretic concentration can be performed with concentration factors of 30–50 depending on the composition. Based on the XRD data for solid composites in AOT, it was concluded that the structure of nanoparticles is most likely of the “core–shell” type with a silver metal core and a surface layer of X-ray amorphous copper.