MORPHOLOGY OF QUASI-2-DIMENSIONAL ELECTRODEPOSITS - A GENERALIZED WAGNER NUMBER

We discuss a generalize Wagner number, a dimensionless system quantity that was applied recently as a tool to analyze the gross features of the morphology of quasi-two-dimensional electrodeposits. This generali zed Wagner number incorporates the main processes involved in electrod eposition (charge transfer across the solid-liquid interface, ionic mi gration within the solution, and mass transport) and treats the LR pot ential drop across the cell. It is pertinent to the gross form of the deposit as well as to its texture and combines these different scales within a single theoretical framework. We present a general derivation , discuss several limiting cases, and suggest criteria for various mor phological behaviors. We give explicit and simple expressions for a re ctangular cell configuration, as an important example, discuss their v alidity, and illustrate the behavior with model calculations.