THE PLATE MATERIALS OF THE LEAD-ACID CELL. PART 3-ANODIC OXIDATION OF TETRAGONAL PBO.
Abstract
Tetragonal PbO (designated PbO-L) was anodized in H2SO4 solution at room temperature, and became converted to a dark-brown-to-metallic-black material resembling PbO2. X-ray diffraction examination of the anodic product showed that it was neither of the known polymorphs of PbO2 but had retained the diffraction pattern of the original tetragonal PbO. The oxidized material had many of the chemical properties of PbO2, an ohmic resistivity of 0.82 ohm-cm, and an open circuit potential in 1.225 sp gr H2SO4, 52 mv above that of beta-PbO2 in the same acid. Chemical analysis showed a stoichiometry of PbO1.91. Crystal morphologies were examined in the electron microscope. Studies on the mechanism of PbO-L oxidation indicate that oxygen may enter the PbO-L lattice as atoms, take two electrons from the Pb present in the lattice and then diffuse through the lattice as ions. Two possibilities for the logical placements of the additional oxygen in the lattice are the fluorite-related LaOF and the PbFC1 layer structure types, both with the same space group as PbO-L, P4/nmm. It is not possible at this time to determine which if either of these possibilities is the actual structure. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 29, 1967
- Accession Number
- AD0664827
Entities
People
- Jeanne Burbank
Organizations
- United States Naval Research Laboratory