The electrochemical oxidation of CH3OH at nanometer-scale PtRu catalyst materials is reported. Comparisons are made between the properties of a Johnson Matthey (JM) PtRu black sample (50 at.% Ru (XRu ≈ 0.5)) and PtRu particles (2-6 nm, nominally XRu ≈ 0.5) prepared by sonication under anhydrous conditions. Cyclic voltammetry and in situ infrared spectroscopy measurements show the catalysts are active for the oxidation, of 0.5 M CH3OH in 0.1 M HClO4 at temperatures between ambient and 70°C. The sonochemically prepared PtRu sample displayed properties characteristic of bulk PtRu alloys with XRu ≈ 0.5. Evidence for phase separation of Pt and Ru was observed in CO stripping voltammetry from the JM catalyst adsorbed at low metal loadings (20 μg/cm2) on bulk Au electrodes. Per gram of catalyst, the JM material was more active toward CO 2 formation and displayed greater resistance to poisoning by adsorbed CO than the sonochemically prepared material during ambient temperature oxidation of 0.5 M CH3OH in 0.1 M HClO4.
|Number of pages||9|
|State||Published - Dec 1 2004|
|Event||Proceedings of the 9th International Fischer Symposium - Munich, Germany|
Duration: Jul 21 2003 → Jul 23 2003
- Electrochemical methods