Electrocatalyst Stability In PEMFCs And The Role Of Fuel Starvation And Cell Reversal Tolerant Anodes

Abstract

Gross fuel starvation at the anode of a proton exchange membrane fuel cell (PEMFC) can result in cell reversal. High positive anode potentials are reached to sustain the current by water oxidation and carbon corrosion at the Pt based anode electrocatalysts. The membrane electrode assembly (MEA) is irreversibly damaged and the flow field plates and stack material in electrical contact with the MEA can be corroded. One of the best approaches to minimise the impact of fuel starvation is to build cell reversal tolerance into the MEA.Moving to more corrosion resistant carbon supports, adding Teflon to the anode catalyst layer to retain water, and deploying a water oxidation electrocatalyst in the anode significantly improved the cell reversal tolerance of the MEA.