Mathematical modeling of electrochemical alloy deposition

Mathematical modeling of charge transfer coupled alloy deposition phenomena is discussed based on recent theoretical and experimental studies. The so called induced codeposition of molybdenum with nickel, cobalt and iron is used as an example to illustrate modeling of catalytic effects in codeposition. Literature models for the so called anomalous codeposition of nickel with iron are evoked which illustrate inhibition effects in codeposition. New experimental data on iron-nickel alloys are presented which suggest that not only iron inhibits the partial reaction of nickel but in addition nickel may catalyze the deposition of iron. A similar behavior is also found for iron-cobalt and cobalt-nickel alloys. A set of rate equations is proposed which includes catalytic and inhibiting effects in codeposition and which provides a unifying framework for the mathematical description of charge transfer coupled alloy deposition phenomena including anomalous and induced codeposition.