New Polymeric Binders for the Preparation and Optimization of Pt/C-Based Electrodes for Proton-Exchange Membrane Fuel Cells (PEMFCs)

Polymeric ionomers are essential to the catalyst layer (CL) of proton-exchange membrane fuel cells (PEMFCs). This study compares two ionomers: the short-side-chain (SSC) N+125D and a high-oxygen-permeability experimental ionomer grade (EIG), the latter intended to enhance oxygen mass transport and the oxygen reduction reaction (ORR). The research evaluates ionomer–solvent interactions across various water/1-propanol mixtures to ensure structural integrity and homogeneous distribution of the electrocatalyst. Multiple ink formulations were analyzed using advanced physical–chemical characterization to determine stability and quality. These insights guided the optimization of the electrode's microstructure for integration into membrane electrode assemblies (MEAs). By employing a multidisciplinary approach, the study correlates ink formulation and electrode morphology with electrochemical performance. This integrated methodology provides a robust framework for optimizing next-generation PEMFC electrodes through a deeper understanding of ionomer behavior and structural influence within the CL.