Electro-oxidation of methanol and ethanol on Pt–Ru/C and Pt–Ru–Mo/C electrocatalysts prepared by Bönnemannʹs method

Pt–Ru/C and Pt–Ru–Mo/C electrocatalysts prepared by Bönnemannʹs method have been studied as porous thin films on high surface area carbon electrodes, in order to evaluate their electroactivity on CO desorption in PEM fuel cells. Electrode precursor powders with and without thermal treatment were considered for comparison. The morphology of these precursor powders was characterized in a high-resolution transmission electron microscope equipped with a nano-EDX device and also by XPS measurements. Cyclic voltammetry showed that addition of Mo in the well-established Pt/Ru system is very promising for methanol and ethanol oxidation. Infrared spectroscopic measurements revealed that a thermal treatment in a hydrogen atmosphere of the electrode precursor material was necessary to enhance the efficiency. In order to compare the electroactivity of different catalysts a normalization procedure based on the amount of Pt was used.