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The effect of various alkaline metal ions on electrochemical behavior of lead electrode in sulfuric acid solution has been investigated. It was found that “the specific anodic oxidation peak” appears at the cathodic scan in cyclic voltammogram of lead electrode in sulfuric acid solution containing Li 2 SO 4 , K 2 SO 4 , Na 2 SO 4 , Rb 2 SO 4 , or Cs 2 SO 4 . The height of the specific anodic oxidation peak varies with the alkaline sulfate in the solution; K 2 SO 4 >> Na 2 SO 4 > Cs 2 SO 4 > Rb 2 SO 4 > Li 2 SO 4 . It should be note that alkaline ions exist in lead sulfate formed on lead electrode in sulfuric acid solution containing potassium sulfate when the electrode was immersed in the solution at the rest potential for more than 1 h. [ABSTRACT FROM AUTHOR]

Abstract: The effect of lignosulfonate (LS) on electrochemical reaction of lead electrode (as a model of negative electrode) has been investigated in 1M, 3M, or 7.1M H2SO4 aqueous solution with 0, 10, 100 or 1000mgl−1 of LS using cyclic voltammetry (CV) combined with in situ electrochemical atomic force microscopy (EC-AFM), as well as rotating ring disk electrode (RRDE). The anodic peaks of the CVs, which correspond to overall reaction of , shifted positive when LS was added or the concentration of H2SO4 was lower. The anodic capacities of the CVs increased with addition of LS when the concentration of H2SO4 was lower. When LS was added, the anodic capacities of the CVs usually increased especially in less concentrated H2SO4 solution at higher sweep rate, while the anodic capacity slightly decreased in 7.1M H2SO4 solution with addition of LS at sweep rate of 10mVmin−1; that is, in most concentrated H2SO4 solution at lower sweep rate in this paper. Two cathodic peaks of the CVs were observed when LS was added, and the peak at lower potential shifted more negative with increase of LS. Lead sulfate crystals dissolved at more negative potential with increase of LS. LS up-took Pb2+ ions in H2SO4 aqueous solution during discharging. [Copyright &y& Elsevier]

The decay of nano-islands on the surface of a Au(111) electrode, in contact with 50 mM sulfuric acid aqueous solution under an applied potential in the range of 0.15–1.2 V, has been investigated using electrochemical atomic force microscopy (EC-AFM). The results are compared with those previously obtained for Au(100). With either orientation, it is found that the area of the top layer of multi-layered islands decreases linearly with time at any applied potential. It was also found that the decay rate, defined as the rate of decrease of the number of atoms in the top-layer of the islands per second, increases with the magnitude of the applied potential. Further, the decay rate of the top layer of the islands on Au(111) is almost the same as that on Au(100). [Copyright &y& Elsevier]

The reaction between lignin and the surface oxide layer on Pb plates was studied by dipping experiments in ultra pure water with lignin, anodic polarograms in sulfuric acid solution with or without lignin and also scanning electron microscopy (SEM) observations of the sample surface after anodic polarization. It is found that the lignin reacts with the surface oxide on the Pb plates in ultra pure water with lignin to reaction products containing Pb and the lignin and they grew preferentially at the interface between Pb and the surface oxide. The deposits formed on the surface suppress to passivate the Pb surface under sulfuric acid solution. [Copyright &y& Elsevier]