Kinetic Study of the Hydrogen Oxidation Reaction on Membrane Coated Electrodes. Part II: Applications

In the Part I of the present work, theoretical expressions for the analysis of the hydrogen oxidation reaction on electrodes covered with layers of polymeric membranes were derived. The diffusion of molecular hydrogen through the different layers and interfaces was taken into account, the kinetic treatment was based on the Volmer-Heyrovsky-Tafel mechanism and a Frumkin type adsorption was applied to the reaction intermediate. The resulting expressions were used to correlate experimental data measured by J. Maruyama et al. (J. Electroanal. Chem. 1998, 447, 201-209), obtained on a rotating platinum electrode covered with a Nafion membrane and on the corresponding bare electrode. A complete set of kinetic and mass transport parameters was obtained in both cases. The applicability of the Levich-Koutecky diagrams for the evaluation of the faradaic current-potential curves was also analyzed and discussed.