ESCA spectra of seven different lead-oxygen species are examined including adsorbed oxygen on lead, two crystal forms of PbO, Pb3O4, PbO2, and two forms of adsorbed water on PbO2. The spectrum of Pbs04 exhibits the behavior to two PbO molecules and one PbO2 molecule although specific characterization of the crystal structure of PbO in Pb3O4 could not be made. The binding energies of the Pb 4f electrons in PbO2 are found to be lower than those of the Pb 4f electrons in PbO. The apparent revesal is rationalized in terms of a relaxation effect. Two kinds of adsorbed water are also found on PbO2- These are explained in terms of a surface adsorbed water species and a water or hydroxyl species which occupies lattice vacancies near the surface. These spectra were then used to characterize electrochemically generated Pb02. It is proposed that this technique may prove valuable in characterizing these electrochemically produced materials.
All Science Journal Classification (ASJC) codes
- Analytical Chemistry