Computer Simulation of the Collisional Generation of Bimetallic nanoparicles

S. A. PAZ; E. P. M. LEIVA; J. JELLINEK; M. M. MARISCAL

Cancun

Congreso; XIX International Materials Reserch Congress; 2010

Materials Research Society (MRS) y la Sociedad Mexicana de Materiales (MRS-Mexico)

The important catalytic properties[1,2] and biological application[3] of bimetallic nanoparticles (BMN) depend strongly on their morphology and composition. Recently, we have proposed a new methodology for the synthesis of BMN based on collisions of two nanoparticles made of different metals[4]. In the present work we show how the morphology and composition of the obtained BMN depends not only on the nature of the colliding nanoparticles, but also on the initial parameters for the collision, such as impact parameter and kinetic energy. Furthermore, we find that the control of these parameters could be used to control the morphology of systems with the same metal composition, leading to different shapes (i.e from nanorods to core/shell structures). Different types of events are found upon collision, such as surface diffusion and local atomic rearrangements. Choosing Au-Pt as a prototype system, we present a detailed study of these processes. [1] C. Henry, Surface Science Reports, vol. 31, 1998, pp. 231-325. [2] M.O. Nutt, J.B. Hughes, and S.W. Michael, Environ. Sci. Technol.vol. 39, 2005, pp. 1346-53. [3] I.H. El-Sayed, X. Huang, and M.A. El-Sayed, Nano Letters, vol. 5, 2005, p. 829–834. [4] M.M. Mariscal, S.A. Dassie, and E.P. Leiva, J. of Chem. Phys., vol. 123, 2005, p. 184505.