Electrochemical behavior of superconducting Bi1.4Pb0.6Sr2Ca2Cu3O10 in halide-containing acetate buffer

Electrochemical responses of Bi1.4Pb0.6Sr2Ca2Cu3O10 in various buffered halide solutions were studied. Electrochemical surface alterations in the anodic and cathodic potentials were investigated by x-ray diffraction (XRD) of the surfaces after potentiostatic exposures in the different media. The principal electrochemical reactions involved in alteration of the surface of the superconductor were identified by considering its potentiodynamic response as well as the post-exposure surface constitution. Formation and stability of bismuth (Bi) and bismuth trioxide (Bi2O3) were found to be significant in deciding the surface composition after electrochemical exposure in acetate buffer and buffers containing chloride (Cl-) and fluoride (F-). The electrochemical process was controlled by chemical reaction and diffusion in the presence of iodide (I-).