A multi-anode, proton exchange membrane electrolysis cell has been used to evaluate commercial and developmental catalysts for the oxidation of methanol, ethanol, ethylene glycol, and glycerol at 80 degrees C. By operating the cell in crossover mode, with the fuel supplied to the cathode, steady-state mass transport limited currents can be achieved. This provides a measure of the stoichiometry of the reaction, which is controlled by the product distribution. The method has been benchmarked by using commercial PtRu black and carbon supported catalysts with 20% and 70% Pt. In all cases, the PtRu alloy decreased onset and half-wave potentials relative to Pt. However, stoichiometries for ethanol, ethylene glycol, and glycerol oxidation were greatly decreased by the presence of Ru. This effect was mitigated by employing Ru as the core in Ru@Pt nanoparticles or in a mixed Ru + Sn oxide support material. Although not as effective as the PtRu alloy for promoting low potential activity, these catalysts exhibited selectivity similar to Pt. Use of alloyed Rh and a Rh core was also evaluated, but did not show any benefits over Pt alone. (C) The Author(s) 2019. Published by ECS.