Perfluorinated Sulfonic Acid-Based Ionomers: Current State and Prospects

This review summarizes the current state of research on perfluorinated sulfonic acid (PFSA) ionomers, including both classic Nafion and a wide range of alternative chemical modifications, as well as new-generation composite and stabilized membranes. The accumulation of a large body of experimental and modeling data in recent years highlights the need to rethink the differences between traditional ionomers and their modern counterparts, which is especially relevant in light of the development of new materials and their expanding applications. PFSA ionomers have a rich research history, playing a key role in the development of polymer-electrolyte fuel cell technologies and other electrochemical systems. At the same time, these materials have become a unique interdisciplinary platform, stimulating the development of new methods of characterization, modeling, and analysis. In PFSA research, technological progress is closely intertwined with fundamental science, encompassing electrochemistry, polymer physics, mechanics, chemistry, and multiscale modeling. The data we collected allowed us to identify new structural and functional patterns, analyze the behavior of ionomers in various states-from thin films and interfaces to bulk membranes-and summarize numerous previously fragmented relationships.