In this paper, we report investigations of the structure and electronic properties of a well-defined Pt/tungsten oxide system prepared on W(110) single-crystal surface. The crystallographic structure and epitaxial orientation were determined by reflexion high-energy electron diffraction.
The chemical state of the film was investigated by photoelectron spectroscopy induced by an X-ray source as well as by synchrotron radiation photoelectron spectroscopy. The ultrathin Pt layers were deposited on the surface of epitaxial tungsten oxide with (111) planes parallel to the W(110).
The formation of three-dimensional Pt clusters with (111) epitaxial plane was observed. It is shown that the Pt deposit caused a partial reduction of the tungsten oxide layer.
We found that it is an electronic effect in which the interaction of the Pt deposit with the tungsten oxide enables charge transfer from the W cation to the O anion leading to change of the chemical state.