STP1188

    Kramers-Kronig Transformation in Relation to the Interface Regulating Device

    Published: Jan 1993


      Format Pages Price  
    PDF Version (232K) 14 $25   ADD TO CART
    Complete Source PDF (7.3M) 14 $119   ADD TO CART


    Abstract

    The Kramers-Kronig transforms constitute in principle a powerful tool to validate experimental impedance data. However, some ambiguities remain in this method; thus, its use needs some care. For instance, the negative resistance generated by the passivation process is often considered an impedance feature that cannot be verified by the Kramers-Kronig transforms. Clarifying this fundamental aspect on the basis of experimental results is not easy. To overcome this difficulty, the problem is addressed in this paper by considering impedance functions numerically simulated by a simple dummy cell. Then the applicability of the Kramers-Kronig transform is verified by evaluating: (a) The real part of the impedance from its imaginary part, (b) The imaginary part of the impedance from its real part, (c) The real part of the admittance from its imaginary part, and (d) The imaginary part of the admittance from its real part. The calculated impedance spectra are then compared with the original ones.

    From these calculations for different types of impedance, it is concluded that the choice of the proper immittance to be submitted to the Kramers-Kronig criterion is of basic importance. If the impedance is measured under potential regulation, the validity test should be performed with admittance. Conversely, if transfer functions are obtained under current regulation, the Kramers-Kronig transform should be applied to the electrode impedance.

    Keywords:

    stability, electrochemical impedance spectroscopy (EIS), passivation, transpassive dissolution, validation criterion


    Author Information:

    Gabrielli, C
    Directeur de Recherche, CNRS, Physique des Liquides et Électrochimie, Laboratoire de l'Université P&M Curie, Paris,

    Keddam, M
    Directeur de Recherche, CNRS, Physique des Liquides et Électrochimie, Laboratoire de l'Université P&M Curie, Paris,

    Takenouti, H
    Directeur de Recherche, CNRS, Physique des Liquides et Électrochimie, Laboratoire de l'Université P&M Curie, Paris,


    Paper ID: STP18067S

    Committee/Subcommittee: G01.11

    DOI: 10.1520/STP18067S


    CrossRef ASTM International is a member of CrossRef.