METHANOL-TOLERANT ELECTROCATALYSTS FOR OXYGEN REDUCTION IN A POLYMER ELECTROLYTE MEMBRANE FUEL-CELL

Heat-treated mu-oxo-iron(III) tetramethoxy phenyl porphyrin (Fe-TMPP)( 2)O and iron(III) tetramethoxy phenyl porphyrin (FeTMPP-Cl) as well as iron(III) octaethyl porphyrin (FeOEP-Cl) adsorbed on high-area carbon s such as deashed and un-deashed RE carbon (Calgon) and Black Pearls-2 000 (Cabot) have been found to exhibit stable and very high oxygen red uction rates. Experiments done over a period of 24 h showed no perform ance degradation. Measured performances were very similar to supported platinum (E-Tek), when tested in 85% H3PO4-equilibrated Nafion(R) 117 membrane at 125 degrees C and hydrated-Nafion(R) membrane at 60 degre es C in a minifuel cell. The macrocycle cathodes are insensitive to th e presence of methanol whereas the platinum cathodes are very sensitiv e and show degradation in the oxygen reduction performance.