Abstract
Cu-Zn composite nanoparticles were prepared by the condensation of Zn vapor onto flying Cu nanoparticles which were produced in advance by a gas-evaporation technique. The structural and morphological observation of these nanoparticles was carried out by means of a transmission electron microscope. It was found that most of the particles grown under the appropriate preparation conditions are composed of two phases of Cu-Zn alloy and Zn, where the latter surrounds the former. It is concluded that the particles grow through four steps; first, Cu nanoparticles grow, second, they melt and re-evaporate due to subsequent heating, and third, Zn vapor condenses onto them, and last, the condensed Zn atoms result in be alloyed with Cu atoms in the outer part of the particles.
