onto them from lead(II) nitrate in static or flowing nitric acid. The substrate is usually sand-blasted before the deposition to remove surface oxide and contamination and to increase the surface roughness and adhesion of the coating. Applications Lead dioxide is used in the production of matches, pyrotechnics, dyes and the curing of sulfide polymers. It is also used in the construction of high-voltage lightning arresters. Lead dioxide is used as an anode material in electrochemistry. β-PbO2 is more attractive for this purpose than the α form because it has relatively low resistivity, good corrosion resistance even in low-pH medium, and a high overvoltage for the evolution of oxygen in sulfuric- and nitric-acid-based electrolytes. Lead dioxide can also withstand chlorine evolution in hydrochloric acid. Lead dioxide anodes are inexpensive and were once used instead of conventional platinum and graphite electrodes for regenerating potassium dichromate. They were also applied as oxygen anodes for electroplating copper and zinc in sulfate baths. In organic synthesis, lead dioxide anodes were applied for the production of glyoxylic acid from oxalic acid in a sulfuric acid electrolyte. Lead acid battery The most important use of lead dioxide is as the cathode of lead acid batteries. Its utility arises from the anomalous metallic conductivity of PbO2. The lead acid battery stores and releases energy by shifting the equilibrium (a comproportionation) between metallic lead, lead dioxide, and lead(II) salts in sulfuric acid. Pb + PbO2 + 2 + 2 H+ → 2 PbSO4 + 2 H2O E° = +2.05 V Safety Lead compounds are poisons. Lead dioxide is a strong oxidizer, so any contact of skin, eyes with either lead dioxide or its vapours may cause severe injury in the form of burns which can even lead to death. PbO2 is not combustible, but it enhances flammability of other substances and the intensity of the fire. In case of a fire it gives off irritating and toxic fumes. Lead dioxide and other lead compound pose a huge environmental hazard when they are not disposed of properly. it is especially poisonous to aquatic life. References External links National Pollutant Inventory: Lead and Lead Compounds Fact Sheet Oxides Lead(IV) compounds Acidic oxides Pyrotechnic oxidizers Oxidizing agents