Thickness Dependence of Proton-Exchange-Membrane Properties

Polymer-electrolyte membranes (PEMs) are a key component in electrochemical energy conversion devices where their main function is to selectively transport ionic species. Reducing PEM thickness an effective strategy for improving performance by minimizing losses. However, how affects the intrinsic properties of membrane remains unexplored. This work aims understand effect on structure-property relationships 3 M perfluorosulfonic acid (PFSA) ionomer. We carried out systematic investigation range 5–70 ?m examine hydration behavior, morphology, crystallinity, mechanical properties, and gas proton transport, with discussion thermal treatments. The collected dataset demonstrates PFSA exhibit transitions certain structural features below 10 ?m, accompanied increased anisotropy swelling conductivity. Many deviate within 10%–20% without monotonic changes thickness, however, linear correlations observed between thermal-mechanical permeability, although latter less significant. Identifying thickness-dependence could help expand parameter window PEMs, thereby enabling optimization automotive fuel cells, heavy-duty applications, electrolyzers, especially if considered as part dispersion-casting reinforcement strategies.