First principle study of the connection between reactivity and electronic structure of nanostructured Pd surfaces
Abstract
Recent theoretical works suggest that the reactivity of catalysts may be controlled by the characteristics of the electronic structure such as the local (surface) densities of electronic states (LDOS) around the Fermi-level (E_F), and isoelectronic reactivity index w^N(r). Based on the results of our first principles electronic structure calculations, we compare and contrast these characteristics for surfaces with significantly varied surface geometry and coordination. In particular, we compare the reactivity of flat (low Miller index), stepped and kinked (high Miller index) surfaces of Pd as influenced by the adsorption of C and S of several coverages. We find that both C and S suppress LDOS around EF for surface atoms, however the magnitude of the effect depends on the local environment of the Pd atom. Our results are in agreement with the fact that S works as inhibitor for Pd surfaces. The results suggest that C is an inhibitor as well, and the poisoning effect of C can be even stronger than that of S. We discuss the behavior of w^N(r) in the vicinity of the surfaces in the light of its connection the reactivity.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARN38003S