The diffusion of Ag-based bimetallic nanoclusters supported on graphite was studied. Using a molecular dynamics simulation, it was revealed that the Ag clusters exhibited rapid diffusion because of their hexagonal bottom layer. In order to decrease the rate of diffusion, Pt and Ni were added so as to distort the structure of the alloy cluster (the alloying method). It was expected that Pt would provide a stronger force on Ag atoms, and Ni to shorten the bond length and thereby change the structure of Ag cluster. However, the attempt was unsuccessful, because Pt and Ni atoms formed cores inside the Ag clusters. A collision system was therefore designed in which large Ag clusters collided with small Pt or Ni clusters. Upon collision with Pt clusters, the diffusion showed little change, because Pt atoms were substituted at the Ag atomic site and form a perfectly ordered structure. The collision with Ni, however, deforms the bottom layer as well as the overall cluster structure and decreased diffusion. This outcome appoints toward the possibility of further application to the manufacture of durable nanocatalysts.

Molecular Dynamics Simulations of the Diffusion of Bimetallic Nanoclusters Supported on Graphite. Park, J.W., Lee, J.S., Min, C.H., Lee, H.S., Ryu, J.H., Seo, D.H., Lee, H.M.: Journal of Korean Institute of Metals and Materials, 2009, 47[8], 461-5