Core Level and Valence Band Spectra of PbO2 by XPS

Core and valence band spectra were obtained from a PbO2 sample. The XPS data were collected with a VSW HA150 spectrometer equipped with a monochromatic Al Kα x-ray source and a multichannel detector. This report includes the Pb 4f, Pb 5d, Pb 4d, O 1s, C 1s, and valence band photoemission peaks. The XPS analysis showed the presence of small amounts of adventitious carbon, adsorbed water, and hydroxide on the surface of the sample. The valence band spectrum of PbO2 collected with achromic radiation provides limited information because of overlapping with the Mg Kα3/4 satellites associated with the intense Pb 5d and O 2s peaks. The use of monochromatic x-radiation allows one to collect a high resolution valence band spectrum without the interference of these satellite features. This is of particular interest in the study of lead oxides because their XPS valence band spectra present features that can be used successfully to distinguish the different oxide forms.