Prediction of atomic arrangement of Pt-Cu nanoalloy by genetic algorithm

The prediction of atomic arrangements for a nanoalloy is of critical importance in developing a novel catalyst for clean energy applications because these arrangements determine the catalytic activities of a nanoalloy. So, the development of a reliable method for predicting atomic arrangements has become increasingly important. In this study, the atomic arrangements of the Pt-Cu in a truncated octahedron (TOh) shaped nanoalloy of various Pt-Cu compositions were predicted. We developed a genetic algorithm (GA) code to predict atomic arrangements, and this code was combined with classical molecular dynamics (MD) simulations to evaluate the optimality of each atomic arrangement. The GA calculation predicted a predominantly multilayered core-shell structure for the Pt-Cu nanoalloy, regardless of the Pt-Cu composition ratio. The cause of a multilayered core-shell structure in the Pt-Cu nanoalloy can be interpreted by the interaction between the intrinsic properties of Pt and Cu, such as their surface energies and miscibility.