Electronic Structure of an Ultrathin Molybdenum Oxide Film

The electronic structure of an ultra-thin molybdenum oxide film obtained by oxidation of molybdenum at an oxygen pressure of 1 Torr and the effect of adsorption of sodium atoms on its electronic structure are studied by photoelectron spectroscopy. Photoemission spectra from the valence band and core levels of O 2 s , Mo 3 d , Mo 3 p , and Na 1 p are studied upon synchrotron excitation in the photon energy range 80–600 eV. It is shown that in the formed oxide film, molybdenum is in two states: Mo 6+ and Mo 4+ . On the surface of the oxide, oxygen is induced both in the composition of the oxides and in hydroxyl. It was shown that MoO 3 is formed on the surface, and MoO 2 at a distance from the surface. The deposition of Na atoms leads to intercalation of the molybdenum oxide layer.