Dissociative adsorption of methanol on platinum in a PtRu bimetallic electrocatalyst has been studied by an accelerated degradation test and normal pulse voltammetry. PtRu electrodes with a minimum number of potential cycles show the highest electrode rate constant values while the one with platinum-like surface characteristics show the lowest rate constant values, evidencing the promotional effect of Ru. © 2011 Elsevier B.V. All rights reserved.