Experimental and theoretical investigation of the electronic structure of Cu2O and CuO thin films on Cu(110) using x-ray photoelectron and absorption spectroscopy

• Autores: Jiang, Peng; Prendergast, David; Borondics, Ferenc; Porsgaard, Soeren; Giovanetti, Lisandro José; Pach, Elzbieta; Newberg, John; Bluhm, Hendrik; Besenbacher, Flemming; Salmeron, Miquel
• Año de publicación: 2013
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Física; Química; Ab initio calculations; Density functional theory; Copper compounds; Electronic structure; Oxidation; Stoichiometry; Thin films; X-ray absorption spectra; X-ray photoelectron spectra
• Institución: Universidad Nacional de La Plata

The electronic structure of Cu2O and CuO thin films grown on Cu(110) was characterized by X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). The various oxidation states, Cu0, Cu+, and Cu2+, were unambiguously identified and characterized from their XPS and XAS spectra. We show that a clean and stoichiometric surface of CuO requires special environmental conditions to prevent loss of oxygen and contamination by background water. First-principles density functional theory XAS simulations of the oxygen K edge provide understanding of the core to valence transitions in Cu+ and Cu 2+. A novel method to reference x-ray absorption energies based on the energies of isolated atoms is presented.
Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas