Ab Initio Investigation of the Role of Atomic Radius in the Structural Formation of PtnTM55–n (TM = Y, Zr, Nb, Mo, and Tc) Nanoclusters

Abstract

Platinum-based nanoclusters have been widely studied because of the possibility to tune the physical and chemical properties as a function of shape, size, chemical composition, and so forth. Although the Pt composition can be experimentally controllable, the location of the Pt species is a challenge as several physical parameters might play a role, for example, surface energy, segregation energy, atomic radius, charge transfer, strain, and so forth. Here, we report density functional theory calculations for 55-atom PtnTM55–n (TM = Y, Zr, Nb, Mo, and Tc) nanoalloys, which provides new insights. In general, the replacement of TM by Pt atoms increases the relative stability of the nanoalloys, and the maximum stability is reached at Pt-rich compositions (n = 35–42). From our analysis, an increase in the number of heterobonds maximizes the charge transfer among the Pt–TM species, and its magnitude depends on the electronegativity difference, coordination, and location (core or surface) of both species. For mos...