Carbon dioxide yields from a direct ethanol fuel cell have been monitored by using a commercial infrared CO2 monitor. The time dependence is reported as a function of temperature, current density, and anode catalyst (Pt vs. PtRu). Yields increased strongly with temperature, with a Faradaic yield of 76% being obtained at 100 degrees C with a Pt black anode. PtRu gave lower yields than Pt by a factor of ca. 3 at 80 and 100 degrees C, but higher yields than Pt at ambient temperature. The superior ability of PtRu to strip adsorbed CO is important at low temperatures, but not a key factor at 100 degrees C. (C) 2009 Elsevier B.V. All rights reserved.