Effect of ionomer structure on water management in low temperature PEM fuel cells

Fuel cells (FCs) play a pivotal role in achieving net zero goals by efficiently converting hydrogen into electricity. However, water management issues such as flooding can reduce performance by obstructing gas diffusion, while insufficient hydration impedes proton transport, especially when employing proton exchange membranes (PEMs) which require operation at temperatures around 80°C. The Membrane Electrode Assembly (MEA) is the powerhouse of FCs, where the ionomer within the catalyst layer plays a crucial role in transferring ions and anchoring catalysts. This study introduces advanced porous materials, such as cardo Polymer of Intrinsic Microporosity (cardo-PIM-1) and Covalent Organic Frameworks (COF), into the ionomer to modulate hydrophilicity/hydrophobicity and enhance mass transport processes. These enhancements aim to optimize the interfacial dynamics within the MEA, improving both water management and ionic conductivity. Using Small-Angle Neutron Scattering (SANS), we explore how these porous structures influence the microstructure of ionomers in MEAs, seeking to refine material properties for heightened FC efficiency and extended longevity.