Atomistic Simulation Study on the Morphology of the Hydrated Perfluorosulfonic Acid Membrane

Molecular dynamics simulation was used to explore the morphology of hydrated Nafion membranes with different water contents. To quantitatively probe the segregated morphology of the hydrated Nafion membrane, Euler characteristic and surface-to-volume ratio were calculated to describe the morphology variation under the different water content. Simulation results showed that water and sulfonic groups of the membrane formed a porous connected water cluster at the low water content. With increasing water content, the connected water clusters gradually formed a water film to separate the hydrophobic region and then swelled in a single direction. The results well support a recent “film-like model” of the hydrated Nafion membrane [1].

Ref.

[1] Kreuer, K.-D.; Portale, G., A Critical Revision of the Nano-Morphology of Proton Conducting Ionomers and Polyelectrolytes for Fuel Cell Applications. Adv. Funct. Mater. 2013, 23, 5390-5397.