High-spin configuration of Co(III) in nonstoichiometric Co3O4 films. XPS investigations

Nonstoichiometric Co₃O₄ films have been investigated by the XPS technique. Analysis of binding energies and intensities of the Co 3s, Co 2p and O 1s core-level peaks and valence band spectra has led to a conclusion that, in contrast to bulk samples, the high-spin configuration of Co(III) ions in nonstoichiometric Co₃O₄ films is stabilized in the spinel octahedral sublattice. The relation between the electronic structure and the catalytic activity of nonstoichiometric cobalt oxide is discussed.