Anodic oxidation of pure and D.S. (dispersion hardened) lead in sulfuric acid solutions

The anodic oxidation of pure and dispersion hardened lead in 1 N H₂SO₄ was studied potentiostatically in the range - 0.28 to 2.0 volts (SHE). The anode surfaces were observed at various stages on a scanning electron microscope and x-ray diffraction techniques were used to determine the phases present. It was established that by oxidation up to 0.25 v only PbSO₄ is obtained. At potentials between 0.25 and 1.57 v, PbO (tetragonal) is formed beneath the lead sulfate layer. At potentials above 1.57 up to 2.0 v, a layer of ßPbO₂ forms in the outermost part of the anode underlying a layer of PbO (tetragonal) at the lower end of the potential scale and αPbO₂ at the upper. Little difference was noted between the behavior of pure lead and dispersion hardened lead --Abstract, page i