Research of Thermodynamics and Properties of Pb/WC-Zro<sub>2</sub> Inert Electrodes Used in Zinc Electrodeposition

Abstract

This research is to fabricate a Pb/WC-ZrO2 inert electrode used in zinc electrodeposition. First, the potential-pH diagram of Pb-H2O system was constructed and the thermodynamic stable region was calibrated in the diagram. On the basis, the co-deposition of Pb, WC and ZrO2 particles from fluorboric acid solutions was realized on the surface of Pb-4wt%Sb substrate. The results show that deposition amounts of ZrO2 and WC particles in the inert electrodes increase with increasing ZrO2 concentrations in the bath, WC particle is easier to deposit into the inert electrodes than ZrO2 particle. The distribution of WC and ZrO2 particles as the second phase within metal matrix Pb is very uniform. Compared with Pb-1wt%Ag alloy electrode, Pb/9.91wt%WC-3.62wt%ZrO2 inert electrode possesses better catalytic activity of oxygen evolution.