Self-organization in catalyst layers of polymer electrolyte fuel cells

Understanding the factors that control microstructure formation in catalyst layers (CLs) of polymer electrolyte fuel cells is of vital importance for improving the operation of these cells. Here, we employ, for the first time, coarse-grained molecular dynamics simulations to perform a structural analysis of the microphase segregation occurring during the fabrication process of CLs. Our mesoscale simulations provide insights into the structural correlations and dynamical behavior of different phases in the catalyst layer composite. This versatile computational study, moreover, rationalizes how the solvent used in catalyst layer fabrication influences the evolution of stable agglomerated conformations. In this realm, we evaluate dispersion media with distinct dielectric properties in view of capabilities for controlling the sizes of carbon/Pt agglomerates and ionomer domains and the resulting pore network topology. These insights are highly valuable for the structural design of catalyst layers with optimized performance and stability.