Modifying the Adsorption Characteristic of Inert Silica Films by Inserting Anchoring Sites

作者:Ulrich Stefan; Nilius Niklas*; Freund Hans Joachim; Martinez Umberto; Giordano Livia; Pacchioni Gianfranco
来源:Physical Review Letters, 2009, 102(1): 016102.
DOI:10.1103/PhysRevLett.102.016102

摘要

The adsorption properties of thin silica films on Mo(112) have been tailored by embedding single Pd atoms into the nanopores of the oxide material. The embedded Pd is able to anchor metal adatoms that would not bind to the inert silica surface otherwise. Several adsorption structures, e.g., Pd-Pd, Ag-Pd, and Au-Pd complexes, have been prepared in this way and analyzed with the STM and density functional theory. The binding strength of the different adatoms to the surface is determined by the number of electrons in their frontier orbitals, which introduce a repulsive interaction with the oxide electronic states and weaken the covalent bond to the Pd anchor.

  • 出版日期2009-1-9