THE LEAD ANODE IN ALKALINE-SOLUTIONS .3. GROWTH OF THICK PBO FILMS

The mechanism of formation of thick, porous, PbO films at a Pb anode in 1N NaOH solutions was investigated. Film growth initiates by a nucleation process and then proceeds at a rate which is controlled by the increasing resistance of the solution in the narrowing pores of the oxide film. The observed i/E relationships were simulated on the basis of two models of film growth, one involving the spreading of islands of film of constant height, and the other in which nuclei both spread and increase in height until the electrode surface is almost fully covered. The latter model led to a very good fit between the observed and calculated curves. copyright. © 1990, The Electrochemical Society, Inc. All rights reserved.