Molecular dynamics simulation study of the melting of Pd-Pt nanoclusters

Atomic Surface Segregation and Structural Characterization of PdPt Bimetallic Nanoparticles

“…In the case of monometallic systems, this period of linearity is somewhat longer than in the case of nanoalloys and has slight oscillations before the occurrence of the solid-liquid phase transition. The fact that the linear stage in Pt is larger than in Pd nanoparticle can be explained by the fact that the first nanostructure is thermally more stable than the second one as it is known from previous reports [19,36] and consequently, a greater amount of thermal energy is required to melt the particle. As will be seen later, these small oscillations in the curves of potential energy obey to slight morphological and structural changes in the particles, which do not affect much to their original structure.…”

Tomographic Heating Holder forIn SituTEM: Study of Pt/C and PtPd/Al2O3Catalysts as a Function of Temperature

“…For example, molecular dynamics simulations predict that, while at low temperature a PtPd nanoparticle has a core rich in Pt surrounded by a layer enriched in Pd, at the melting temperature Pt may diffuse to the surface (Sankaranarayanan, et al, 2005;Guisbiers et al, 2011). This redistribution of metal is important because heating experiments performed on PtPd particles supported on alumina have shown preferential loss of one of the active components from the catalyst (Pt or Pd) due to the presence of oxygen and differences in the vapor pressures of Pt and Pd oxides (Harris, 1986).…”

Dynamics and Thermodynamics of Nanoclusters

“…In fact, surface melting has been readily observed in simulations of core-shell nanoalloys [20][21][22][23]. A more correct description of the energy dependence of the measured phase space volume for such a trapped system is therefore not the extreme case as given by Equation (7), but one in which we have a different E* for each mixed solid-liquid state.…”