Singular Perturbation Analysis of the Faradaic Impedance of Copper Dissolution Accounting for the Effects of Finite Rates of a Homogeneous Reaction

Abstract

The frequency response of the dissolution of a copper rotating disk in 0.1 N HCl is investigated. Specifically, the effect of accounting for finite rates of the homogeneous complexing reaction is explored by utilizing a perturbation analysis to split the diffusion boundary layer into inner and outer regions so that the salient features of the problem can be examined separately. Formulating the singular perturbation problem lea:ds to a better understanding of the physical nature of the faradaic impedance of the system and enables one to characterize quantitatively the numerical errors resulting from the Stefan-Maxwell impedance algorithm that arise for certain values of the rate constants and frequency range. Complex-plane plots, calculated from the SM model and the perturbation analysis, illustrate the frequency dependence of the faradaic impedance for A different values of the homogeneous rate constant k 6 and allow comparisons to be made.

High‐Rate Copper Dissolution in Hydrochloric Acid Solution

“…3 for different potentials. For the whole potential range, the current is under a mixed control, and the overall current can be analyzed according to the expression 1 I = 10 + I:' + C.'fr" [6] The parameters involved in Eq. 6 were obtained by a fitting procedure and are given in Table I. A nondiffusional current 1,, appears in this potential domain, and its variation is not monotonic with the potential.…”

Corrosion resistance and antibacterial properties of copper coating deposited by cold gas spray

“…It is well known that the CuCl film at the film/solution interface can be partially dissolved to form CuCl2 - [59,60], while at [Cl -] >1 mol/L NaCl, there can be formation of CuCl3 2and CuCl4 3complexes, depending on the chloride ion concentration [61]. For example, the following reaction can occur:…”

EIS and statistical analysis of copper electrodeposition accounting for multi-component transport and reactions

“…Although the computation of impedance using this method is relatively simple, it can lead to ambiguous results because in some cases more than one electrical circuit can represent the same electrochemical process [6]. A different approach is to begin with a physicochemical model including kinetics and/or mass transport effects [7][8][9][10][11][12][13][14][15][16][17][18][19][20]. If a perturbation with a small enough amplitude is applied, then the model can be linearized.…”

“…Other models have included diffusion and convection within the transport equations. Convection is often incorporated as a complex variable called the Warburg impedance in models that consider uncoupled mass transport equations [8][9][10][11][12][13]. This approach involves solving the transport equation for the species that includes diffusion and convection through a semi-infinite boundary layer.…”