Bilayer Anodes for Improved Reformate Tolerance of PEM Fuel Cells

摘要

The concept of bilayer anodes for improved reformate tolerance was analysed using model calculations. It was found that for a bilayer anode to give good results the catalyst in the layer adjacent to the backing should enable CO oxidation at low potentials and have a relatively low rate of H{sub}2 oxidation. The catalyst in the second layer should enable fast H{sub}2 oxidation, and have limited CO adsorption. Experimental results are presented showing that the bilayer anode works especially well with reformate gas. It was found that the water gas shift equilibrium plays an important role in the mechanism for reformate tolerance. The implementation of the bilayer concept seems to be very useful in optimising both CO and CO{sub}2 tolerance of PEMFCs, including at high fuel utilisation.