Tailoring the Structural Motif of AgCo Nanoalloys: Core/Shell versus Janus-like

This paper deals with the computational study of the growth of small silver-cobalt clusters, modeled by a semiempirical potential. Both atom-by-atom growth molecular dynamics and simulations of freezing are used to identify formation patterns of silver-cobalt nanoalloys. Different pathways leading to core/shell and bicompartmentalized configurations, reminiscent of Janus geometry, are observed in cobalt-rich and in silver-rich alloys, respectively. The physical origin of the formation of asymmetric structures and their evolution toward core/shell motifs, as well as the opposite process, are discussed.