The electrochemical behavior of PbSO4 with different structures on Pb

The reduction processes of PbSO4 with different structures on ph have been studied by the linear sweep voltammetry (LSV) and potential step technique. At high overpotential, the reduction rate of PbSO4 depends on the diffusio n of SO42- ions towards hulk solution and Pb2+ ions towards the reaction su rface. The large PbSO4 crystals make the diffusion distance of Pb2+ ions to the reaction surface extend, while the small PbSO4 crystals impede the dif fusion of SO42- ions through the micropores. The accumulation of PbSO4 with out activity occurs in the anodic film. The effects of the H2SO4 concentrat ion and temperature are also discussed. (C) 2000 Elsevier Science S.A. All rights reserved.