Sol–gel silica thin films with copper selenide

The silica sol–gel films with copper selenide produced by the selenization of metallic copper nanoparticles were fabricated. The composition of the films was studied with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and optical absorption spectroscopy. Several copper selenide phases were detected with XRD and contribute into the complicated behavior of core levels (Cu2p, Se3d, and Si2p) and Auger levels (Cu) in the XPS analysis. The optical absorption features of the films in the visible and near-infra red range are presented. The consistent interpretation of experimental data is proposed based on assumption of copper multivalence in the system “particles–silica matrix”.