Core Level and Valence Band Spectra of PbO by XPS

Abstract

Core and valence band spectra were obtained from a commercial PbO. 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, carbonate, adsorbed water, and significant amounts of hydroxide on the surface of the sample. When collected with achromic radiation the valence band region of PbO is overlapped by the Mg Kα3/4 satellites associated with the relatively intense Pb 5d and O 2s peaks. The use of monochromatic x-radiation allowed 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.

Characterization of the patina formed on a low tin bronze exposed to aqueous hydrogen sulfide

“…Lead may segregate to the outer surface of the bronze at the elevated temperatures during casting, and lead surface enrichment has been noted previously for Roman bronzes analyzed by XPS . A Pb 4f doublet was observed for the polished bronze surface, with the Pb 4f 7/2 photoemission peak located at 138.5 eV indicating the presence of Pb (II), probably PbO and/or hydroxide, in this case . It should be noted that while metallic Pb was not observed by XPS on the polished surface, the greater sampling depth of XRD (see succeeding texts) observed only metallic Pb.…”

Iron doping effect on the electronic structure in yttrium aluminosilicate glasses

“…The shoulder at lower binding energy could be assigned to p bonding orbitals and the second one to r bonding orbitals [26]. In the valence band spectra O 2s peaks also occur [27,28]. The photopeak around 25.5 eV corresponds to O 2s core level electrons.…”

“…For the sample without iron, the binding energy of 74.41 eV corresponds to that of alumina. The broadening of the Al 2p by progressive iron addition may be caused by the deformation of aluminum polyhedra [13] assumed to be preponderantly tetracoordinated as have been shown by 27 Al MAS NMR investigation of other yttrium-alumino-silicate glasses [14,15]. [3,16].…”

Wear and frictional mechanisms of copper-based bearing alloys

“…Two other contributions were detected mostly on polished samples at 286.4 ± 0.2 eV and 288.8 ± 0.2 eV and were assigned to C-O groups and to carbonates or carboxylic group, respectively [16,17]. The lead signal Pb 4f 7/2 showed a main contribution at 183.3 ± 0.3 eV and a minor peak at 136.6 ± 0.3 eV corresponding to Pb(+2) and to metallic lead [15,[18][19][20], respectively. Signals of metal oxides Cu(+2), Sn(+4) and Pb(+4) usually present at 933.7 ± 0.3 eV [11,12,21], 486.8 ± 0.3 eV [15,21] and 137.5 ± 0.3 eV [15,21,22], respectively, were absent.…”