Influence of the microporous layer on carbon corrosion in the catalyst layer of a polymer electrolyte membrane fuel cell

► Accelerated Stress Testing (AST) for carbon corrosion in a segmented PEM fuel cell. ► Compared cathode Gas Diffusion Layers (GDLs) with and without a microporous layer. ► Cells with cathode MPL are more resistant to corrosion of the catalyst support. ► Current distribution with cathode MPL changes due to catalyst layer degradation. ► Without cathode MPL, GDL fibers cause localized thinning in the catalyst layer.