Impact of the charge transfer process on the Fe2+/Fe3+distribution at Fe3O4 magnetic surface induced by deposited Pd clusters

Abstract

Magnetic iron oxide particles decorated with transition-metal nanoparticles have become increasingly attractive in catalysis regarding the environment modifications, such as an additive ligand or carrier, which could significantly influence their performances. In this work, we used the Density Functional Theory (DFT) in the gradient approximation to study the interaction between the metal and its support for palladium and palladium oxide clusters on the surface of Fe3O4(001)magnetite. We report a dynamic process promoted by the palladium deposition with charge transfer from the metal host. An increase in the Fe2+/Fe3+ ratio at the topmost surface of the support was determined. The reduction of surface Fe3+ ions with electrons located at the interface has been proposed. Surprisingly, this slight increase in the surface density in Fe2+ ions was not observed in palladium oxide when the charge transfer from the support was significantly enhanced. Finally, the impact of the charge transfer process between the surface and the adsorbed species on palladium in terms of structure stability was discussed.