We propose to investigate how non-localized electrons, those near fermi level, in supported nanoclusters govern catalytic properties. The catalytic properties are determined by the electronic structures of surfaces of catalysts, whereas the electronic structures are determined by many factors. These factors are not independent of each other, but strongly correlated. A precise control of the electronic structure of supported nanoclusters, such as adding one or two electrons to the nanoclusters, is not a ready job. We propose to study the reactivity of Pt and Rh nanoclusters supported on MgO/Ag(001) and CuO/Cu(110), as electrons may tunnel, via the oxide films, between the nanoclusters and metal substrates. By varying the oxides thickness, one may open or shut down the tunneling channel. As varying the oxide thickness alters little the other factors which determine surface electronic structures, this approach allows us to investigate the sole effect of the transferred charge on catalytic properties and furthermore to address the fundamental issue — the effect of non-localized electrons on catalytic properties. The scheduled investigations contain three aspects: preparation and characterization of model systems, monitoring of surface reactions and density-functional-theory simulations. The first two will be performed with various surface probe techniques under ultrahigh vacuum. The latter will confirm the charge transfer between the metal substrates and clusters, and also the effect of transferred electrons by giving the activation barrier and reaction energy for each process in reactions.
|Effective start/end date||1/08/20 → 31/07/21|
- charge transfer
- catalytic model systems
- ultrahigh vacuum
- surface probe techniques
- density-functional-theory calculations