(50e) High-Performance Electrodes for Hydroxide Exchange Membrane Fuel Cells

Hydroxide exchange membrane fuel cells (HEMFCs) are an attractive alternative to conventional proton exchange membrane fuel cells (PEMFCs) because they are compatible with non-precious-metal catalysts. However, HEMFC performance is lower than the PEMFC benchmark, in part because HEMFCs continue to borrow electrode architectures that were originally designed for PEMFCs. In PEMFCs, water is produced at the cathode, so hydrophobic gas diffusion layers (GDLs) are employed to control flooding. But hydrophobic GDLs may not be necessary for HEMFC cathodes, in which water is consumed instead of produced, reversing the direction of water transport in the cell. This work demonstrates that the performance and durability of membrane-electrode assemblies (MEAs) can be improved by tailoring electrode design to reflect the unique kinetics and water transport behavior of HEMFCs.