Catalysis of ethanol electro oxidation by PtRu: the influence of catalyst composition

The catalytic activity for ethanol oxidation is studied as a function of the atomic composition of PtRu electrodeposits. Chronoamperometric curves taken at 0.5 V show that the current for ethanol oxidation at PtRu electrodeposits, measured 30 min after the application of a potential step from 0.05 V, increases in the presence of Ru up to a Ru content of about 40%. The highest value observed at 0.5 V vs. RHE was 30 muA/cm(2) at 25 degreesC. There is a relatively narrow range of PtRu compositions that present a high rate of ethanol oxidation. Pure Ru has no activity towards ethanol oxidation at room temperature. (C) 2004 Elsevier B.V. All rights reserved.