Characterization of Ni2O3⋅6H2O by XPS

We report x-ray photoemission spectra (XPS) of hydrated nickelic oxide (Ni2O3⋅6H2O). XPS spectra were measured with the Physical Electronics Model 5400 x-ray photoelectron spectrometer using unmonochromatized Mg Kα x rays at two pass energy settings corresponding to analyzer energy resolutions of 1.34 and 0.54 eV. We present the survey spectrum (binding energy range of 0–1100 eV) measured at an analyzer energy resolution of 1.34 eV. Multiplexes of the C, O, and Ni photoemission lines, valence band region, as well as the Ni LVV Auger line were measured at an analyzer energy resolution of 0.54 eV. The Ni2O3⋅6H2O sample was obtained commercially from Alfa. Our XPS results show that the near surface region consists of a large proportion of Ni(OH)2. In addition, the sample contains Na and Cl in small quantities. The presence of Na and Cl is probably an artifact of sample preparation procedures.