Lead dioxide-SDS composites: Design and properties

Abstract

Abstract The electrodeposition of PbO2 from a sodium dodecyl sulphate-containing medium has been investigated. The presence of sodium dodecyl sulfate in the deposition electrolyte leads to a slight inhibition of the deposition of lead dioxide. It has been found that the morphology and structure of composite materials differs significantly from lead dioxide. With an increase in the additive content in the composite, there is a transition from large-grained deposits to materials with submicron and nano-sized crystals. It is shown that anionic surfactants, sodium dodecyl sulfate in particular, are included in the growing lead dioxide. The changing in deposition conditions (temperature, pH and anodic current density) allows one to control the content of surfactant in the resulting oxide. It is possible to obtain a surfactant-oxide composite with the content of organic substance in the oxide up to 5.4 wt%. The electocatalytic activity of the materials involved was investigated in respect to oxygen evolution reaction and the oxidation of 4-chlorophenol. Oxygen overpotential on PbO2-SDS coatings decreases in comparison to non-modified sample because of a decrease in the degree of filling of oxygen-containing particles on the surface of the electrode, probably due to blocking by sulfate ions. The 4-chlorophenol oxidation rate is significantly increased on PbO2-SDS composites. Thus, already after 90 min of electrolysis on composites, contained 2 and 4.2 wt% SDS, all aromatic intermediates are destroyed, and only aliphatic acids are found in the solution.