An electrochemical and radiotracer investigation on lead dioxide: Influence of the deposition current and temperature

The properties of electrodeposited PbO2 are sensibly influenced by the deposition current and temperature. In particular, tritium radiotracer measurements demonstrated that protons were incorporated into the bulk of an oxide film and on its surface. The degree of hydration increased with increasing current and decreased with temperature, and was related to the morphological characteristics of the oxide, such as roughness measured by changes in the double layer capacity. Conversely, the amount of hydrogen had negligible effects on the number of free carriers as evaluated from Mott-Schottky plots. The hydration degree of the surface seems to be an important factor influencing electrocatalytic processes at high potentials, such as O2 evolution and O3 formation. On less hydrated, more crystalline PbO2 surfaces, the first process was inhibited and accordingly, the second was favored. Copyright 2013 (CC) SCS.