Journal of Power Sources, Vol.235, 202-213, 2013
Effects of Sm and Y on the electron property of the anodic film on lead in sulfuric acid solution
The influences of Sm and Y on the electron properties of the anodic films on lead at 1.28 V(vs.SCE), 1.5 V(vs.SCE) and 1.8 V(vs.SCE) in 4.5 mol L-1 sulfuric acid are investigated by using electrochemical impedance spectroscopy (EIS), Mott-Schottky plot, galvanic polarization and photo-electrochemical technique. The results show that Sm and Y can significantly decrease the resistances of the anodic films on lead electrode at 1.28 V, 1.5 V and 1.8 V, the oxygen and hydrogen evolutions of lead electrode covered by the anodic film decrease with the addition of Sm or Y. The anodic films on lead electrode at three potentials appear an n-type semi-conductive character, the addition of Sm or Y can decrease the slope of M-S plot of the anodic film, it implying the increment of the defect density within the anodic film, which is beneficial for improving the charge discharge behavior of the lead acid battery. (C) 2013 Elsevier B.V. All rights reserved.
Keywords:Lead alloy;Anodic film;Electrochemical impedance spectra (EIS);Mott-Schottky plot;Rare earth element