Atomistic Simulations of Diffusion and Structural Transformation of Re on W Nanoclusters: Implications for Re–W Catalysts

Abstract

Bimetallic nanoclusters have a wide range of uses, and Re−W has been shown to be a catalyst due to its good properties, so it is crucial to study Re−W nanoclusters at the microscopic scale in order to obtain better-performing Re−W nanoclusters. This research investigates the diffusion and structural modification of Re on the surfaces of W nanoclusters at high temperatures. The EAM potential function is employed in this work to explain the interaction between Re and W, and the LAMMPS (large-scale atom/polar massively parallel simulation) package is used for the simulation. We observed the diffusion phenomenon in our investigation by depositing Re atoms on the surface of the W nanoclusters. The findings demonstrate that there are differences in the exchange energy barriers between the Re and W atoms at various locations. At the intersection of the faces, the more (110) faces there are, the lower the exchange energy barrier between the Re and W atoms. During diffusion, the mechanisms of vacancy formation and migration were investigated. The results of the analysis demonstrate that the formation and migration of these vacancies are facilitated by the presence of Re atoms. Furthermore, we noticed that the lattice structure changed throughout the entire deposition process. This observation offers a theoretical direction for producing Re−W bimetallic nanoclusters with a little lattice distortion.