XPS, UPS, and STM Studies of Nanostructured CuO Films
Journal of Structural Chemistry
, E-ISSN: 1573-8779
||Copper oxide, Nanoparticle, Oxide film, Oxygen, Plasma, STM, Surface, UPS, XPS
G. K. Boreskov Institute of Catalysis, Siberian Division, Russian Academy of Sciences, Novosibirsk
Novosibirsk State University
A Cu1O1.7 oxide film containing a large amout of superstoichiometric oxygen was obtained by low-temperature oxidation of metallic copper in the oxygen plasma. An STM study of the film structure showed that ∼10 nm planar copper oxide nanocrystallites with particles packed parallel to the starting metal surface. In an XPS study, the spectral characteristics of the Cu2p and O1s lines indicated that particles with a CuO lattice formed (E bnd(Cu2p 3/2) = 933.3 eV and a shake-up satellite, E bnd(O1s) = 529.3 eV). The additional superstoichiometric oxygen is localized at the sites of contact of nanoparticles in the interunit space and is characterized by a state with the binding energy E bnd(O1s) = 531.2 eV. Due to the formation of a nanostructure in the films during low-temperature plasma oxidation, the resulting copper oxide has a much lower thermal stability than crystalline oxide CuO.