Effects of Ink Formulation on Construction of Catalyst Layers for High-Performance Polymer Electrolyte Membrane Fuel Cells

Rational design of catalyst layers in a membrane electrode assembly (MEA) is crucial for achieving high-performance polymer electrolyte fuel cells. Establishing clear understanding the property (catalyst ink)–structure layer)–performance relationship lays foundation this rational design. In work, synergistic approach was taken to correlate ink formulation, microstructure layers, and resulting MEA performance establish such property–structure–performance relationship. The solvent composition (n-PA/H2O mixtures) demonstrated strong influence on fabricated with an 830-EW (Aquivion) ionomer, especially polarization losses cell activation mass transport. differences were studied terms how affects catalyst/ionomer interface, ionomer network, pore structure layers. aggregates mainly covered surface acting as oxygen reduction reaction active sites, aggregate sizes (revealed by ultrasmall angle X-ray scattering cryo-transmission electron microscopy) dictated tuning composition, which turn determined interface (available sites). n-PA/H2O mixtures 50?90 wt % H2O, agglomerates could be effectively broken up into small aggregates, leading enhanced kinetic activities. boiling point mixed solvents ultimate evidenced mercury porosimetry scanning microscopy. For higher point, catalyst–ionomer tend agglomerate during evaporation process finally form larger layer, more secondary pores thus lower transport resistance. Both enlarged appropriate achieved layer from mixture 90 best performance.