Valence state of Manganium in a MnCoO ceramics

Manganium -cobalt based ceramics materials were produced by solid state reaction and sintred in a furnance in air atmosphere for 20h. Annealing temperature was 600 Celsius degree. For investigations a series of samples, with a various composition was chosen: MnCoO, Mn, Co2O and Mn2CoO. In order to determine valence states of the Mn, X-Ray photoemission spectroscopy (XPS) analysis were performed at room temperature under a pressure below 1.1 × 10−9 mBar. The photoelectrons were excited by an Mg-Kα X-Ray anode operated at 15 keV and 300 W. Omicron Argus hemispherical electron analyser with a round aperture of 4 mm was used for the analysis of emitted photoelectrons. Measurements were carried out in a constant analyser energy (CAE) mode with pass energy equal 50 eV. To remove contaminations and oxides, the surface was etched before the measurement. Argon ion gun with energy up to 5 keV was used for 5 min. etching. Two regions were measured: Mn2p and Mn3s. Measurements shoved domination of Mn3+ in a materials.