塩化物および硫酸塩溶液中における鉛-白金および鉛-パラジウム複合電極の陽極的挙動

Abstract

Considerable interests have been aroused in the use of Pb-Pt and Pb-Pd bielectrodes counting for expensive Pt electrodes and corrodible lead dioxide ones.In this study anodic polarization curves of these electrodes were measured by a potentiostat. The results obtained were as follows:In the case of the Pb electrode in NaCl solution, the anodic current density took a minimum value at 1.4V, a maximum at 1.6V and another minimum at 1.75V, then increasing in proportion to the anodic potential, while for the anodic current density in Na2SO4 solution an ever increasing curve was obtained with increasing anodic potential. On the other hand, with the Pb-Pt bielectrode, only one minimum was seen between 0.6 and 0.9V, while with the Pb-Pd bielectrode the behavior curve was remarkably different indicating a steeper increase of the current density at -0.23V and a passive state between 0.8 and 1.1V. The anodic current between -0.2 and 0V probably derived from dissolution of palladium and above 0V oxygen evolved.The electronic deflection revealed no annular pattern, thus suggesting non-crystalline deposit on the electrode surface in sodium sulfate solution.So far as we studied, the Pb-Pd bielectrode has been proved to withstand the process of electrolysis in artificial sea water.