Front Dynamics during Diffusion-Limited Corrosion of Ramified Electrodeposits

Abstract

Experiments on the diffusion-limited corrosion of porous copper clusters in thin gap cells containing cupric chloride are reported. By carefully comparing corrosion front velocities and concentration profiles obtained by phase-shift interferometry with theoretical predictions, it is demonstrated that this process is well-described by a one-dimensional mean-field model for the generic reaction A + B (static) → C (inert) with only diffusing reactant (cupric chloride) and one static reactant (copper) reacting to produce an inert product (cuprous chloride). The interpretation of the experiments is aided by a mathematical analysis of the model equations which allows the reaction-order and the transference number of the diffusing species to be inferred. Physical arguments are given to explain the surprising relevance of the one-dimensional mean-field model in spite of the complex (fractal) structure of the copper clusters.

Corrosion Accelerating Surface Catalysts

“…Me ^^ Me n+ + ne (12) nFe 3+ + ne nFe 2+ (13) The Fe 2+ ions formed in the course of corrosion are spontaneously reoxidized to Fe 3+ , while in agreement with Eq. (7), an equivalent amount of oxygen is ionized.…”

“…In the fabrication of integrated circuits, in the activation of atmospheric oxygen both redox systems are effective and this results in the etching of surplus copper.In the case of metal corrosion,(12) and the process Cu 2+ (C1") + e Cu + (C1") In the fabrication of integrated circuits, in the activation of atmospheric oxygen both redox systems are effective and this results in the etching of surplus copper.In the case of metal corrosion,(12) and the process Cu 2+ (C1") + e Cu + (C1")…”

Asymptotics of reaction–diffusion fronts with one static and one diffusing reactant

“…6. These results may be used to infer reaction orders and perhaps even kinetic constants in diffusion-limited corrosion experiments from transient decay measurements of the reaction-rate density in the diffusion layer [3].…”

Porous bead-based microfluidic assay: theory and confocal microscope imaging

“…Experiments by Leger et al (1999), examining front dynamics during diffusion-limited corrosion of ramified electrodeposits, found that after long times the reaction front position was given by the power law P D * t 0.5 .…”