Using density functional calculations to elucidate atomic ordering of Pd-Rh nanoparticles at sizes relevant for catalytic applications
L. Vega, H. A. Aleksandrov, K. M. Neyman.
Chinese J. Catal., 40 (2019) 1749
DFT modelling identifies surface composition of Pd-Rh particles of thousands atoms and paves the way for evaluating surface segregation due to adsorbed reactants.
This study quantifies, with the help of density functional (DFT) calculations and our novel Topological Approach, atomic ordering and surface segregation effects in Pd-Rh particles with compositions 1:3, 1:1 and 3:1 containing up to 201 atoms (ca. 1.7 nm). The obtained data are used to reliably optimise energetically preferred atomic orderings in inaccessible by DFT Pd-Rh particles containing thousands of atoms and exhibiting sizes exceeding 5 nm, which are typical for catalytic metal particles. It is outlined, how segregation effects on the surface arrangement of Pd-Rh nanoalloy catalysts induced by adsorbates can be evaluated in a simple way within the present modelling setup.